diff --git a/test/helper.lua b/test/helper.lua
index 669dec07..f355efed 100644
--- a/test/helper.lua
+++ b/test/helper.lua
@@ -466,4 +466,14 @@ function helpers.reload_roles(srv)
     t.assert_equals({ok, err}, {true, nil})
 end
 
+function helpers.get_map_reduces_stat(router, space_name)
+    return router:eval([[
+        local stats = require('crud').stats(...)
+        if stats.select == nil then
+            return 0
+        end
+        return stats.select.details.map_reduces
+    ]], { space_name })
+end
+
 return helpers
diff --git a/test/helpers/storage_stat.lua b/test/helpers/storage_stat.lua
deleted file mode 100644
index 2bb4dcd4..00000000
--- a/test/helpers/storage_stat.lua
+++ /dev/null
@@ -1,118 +0,0 @@
-local checks = require('checks')
-local helpers = require('test.helper')
-
-local storage_stat = {}
-
--- Wrap crud's select_on_storage()/count_on_storage()
--- function to count selects/counts and add storage_stat()
--- function that returns resulting statistics.
---
--- Call it after crud's initialization.
-function storage_stat.init_on_storage(method_on_storage_name)
-    assert(_G._crud[method_on_storage_name] ~= nil)
-
-    -- Here we count requests.
-    local storage_stat_table = {
-        requests = 0,
-    }
-
-    -- Wrap method on storage function.
-    local requests_on_storage_saved = _G._crud[method_on_storage_name]
-    _G._crud[method_on_storage_name] = function(...)
-        local requests = storage_stat_table.requests
-        storage_stat_table.requests = requests + 1
-        return requests_on_storage_saved(...)
-    end
-
-    -- Accessor for the statistics.
-    rawset(_G, 'storage_stat', function()
-        return storage_stat_table
-    end)
-end
-
-function storage_stat.init_on_storage_for_select()
-    storage_stat.init_on_storage('select_on_storage')
-end
-
-function storage_stat.init_on_storage_for_count()
-    storage_stat.init_on_storage('count_on_storage')
-end
-
--- Accumulate statistics from storages.
---
--- The statistics is grouped by replicasets.
---
--- Example of a return value:
---
---  | {
---  |     ['s-1'] = {
---  |         select_requests = 1,
---  |     },
---  |     ['s-2'] = {
---  |         select_requests = 0,
---  |     },
---  | }
-function storage_stat.collect(cluster)
-    checks('table')
-
-    local res = {}
-
-    helpers.call_on_storages(cluster, function(server, replicaset)
-        checks('table', 'table')
-
-        -- Collect the statistics.
-        local storage_stat = server.net_box:call('storage_stat')
-
-        -- Initialize if needed.
-        if res[replicaset.alias] == nil then
-            res[replicaset.alias] = {}
-        end
-
-        -- Accumulate the collected statistics.
-        for key, val in pairs(storage_stat) do
-            local old = res[replicaset.alias][key] or 0
-            res[replicaset.alias][key] = old + val
-        end
-    end)
-
-    return res
-end
-
--- Difference between 'a' and 'b' storage statistics.
---
--- The return value structure is the same as for
--- storage_stat.collect().
-function storage_stat.diff(a, b)
-    checks('table', 'table')
-
-    local diff = table.deepcopy(a)
-
-    for replicaset_alias, stat_b in pairs(b) do
-        -- Initialize if needed.
-        if diff[replicaset_alias] == nil then
-            diff[replicaset_alias] = {}
-        end
-
-        -- Substract 'b' statistics from 'a'.
-        for key, val in pairs(stat_b) do
-            local old = diff[replicaset_alias][key] or 0
-            diff[replicaset_alias][key] = old - val
-        end
-    end
-
-    return diff
-end
-
--- Accepts collect (or diff) return value and returns
--- total number of select/count requests across all storages.
-function storage_stat.total(stats)
-    local total = 0
-
-    for _, stat in pairs(stats) do
-        total = total + (stat.requests or 0)
-    end
-
-    return total
-end
-
-return storage_stat
diff --git a/test/integration/count_test.lua b/test/integration/count_test.lua
index 9fb62a10..008ea788 100644
--- a/test/integration/count_test.lua
+++ b/test/integration/count_test.lua
@@ -4,7 +4,6 @@ local clock = require('clock')
 local t = require('luatest')
 
 local helpers = require('test.helper')
-local storage_stat = require('test.helpers.storage_stat')
 
 local pgroup = t.group('count', {
     {engine = 'memtx'},
@@ -24,12 +23,9 @@ pgroup.before_all(function(g)
 
     g.cluster:start()
 
-    helpers.call_on_storages(g.cluster, function(server)
-        server.net_box:eval([[
-            local storage_stat = require('test.helpers.storage_stat')
-            storage_stat.init_on_storage_for_count()
-        ]])
-    end)
+    g.cluster:server('router').net_box:eval([[
+        require('crud').cfg{ stats = true }
+    ]])
 end)
 
 pgroup.after_all(function(g) helpers.stop_cluster(g.cluster) end)
@@ -583,7 +579,8 @@ pgroup.test_count_no_map_reduce = function(g)
         },
     })
 
-    local stat_a = storage_stat.collect(g.cluster)
+    local router = g.cluster:server('router').net_box
+    local map_reduces_before = helpers.get_map_reduces_stat(router, 'customers')
 
     -- Case: no conditions, just bucket id.
     local result, err = g.cluster.main_server.net_box:call('crud.count', {
@@ -594,15 +591,9 @@ pgroup.test_count_no_map_reduce = function(g)
     t.assert_equals(err, nil)
     t.assert_equals(result, 1)
 
-    local stat_b = storage_stat.collect(g.cluster)
-    t.assert_equals(storage_stat.diff(stat_b, stat_a), {
-        ['s-1'] = {
-            requests = 1,
-        },
-        ['s-2'] = {
-            requests = 0,
-        },
-    })
+    local map_reduces_after_1 = helpers.get_map_reduces_stat(router, 'customers')
+    local diff_1 = map_reduces_after_1 - map_reduces_before
+    t.assert_equals(diff_1, 0, 'Count request was not a map reduce')
 
     -- Case: EQ on secondary index, which is not in the sharding
     -- index (primary index in the case).
@@ -614,15 +605,9 @@ pgroup.test_count_no_map_reduce = function(g)
     t.assert_equals(err, nil)
     t.assert_equals(result, 1)
 
-    local stat_c = storage_stat.collect(g.cluster)
-    t.assert_equals(storage_stat.diff(stat_c, stat_b), {
-        ['s-1'] = {
-            requests = 0,
-        },
-        ['s-2'] = {
-            requests = 1,
-        },
-    })
+    local map_reduces_after_2 = helpers.get_map_reduces_stat(router, 'customers')
+    local diff_2 = map_reduces_after_2 - map_reduces_after_1
+    t.assert_equals(diff_2, 0, 'Count request was not a map reduce')
 end
 
 pgroup.test_count_timeout = function(g)
diff --git a/test/integration/ddl_sharding_key_test.lua b/test/integration/ddl_sharding_key_test.lua
index 8a874ad0..da02b54d 100644
--- a/test/integration/ddl_sharding_key_test.lua
+++ b/test/integration/ddl_sharding_key_test.lua
@@ -3,7 +3,6 @@ local crud = require('crud')
 local t = require('luatest')
 
 local helpers = require('test.helper')
-local storage_stat = require('test.helpers.storage_stat')
 
 local ok = pcall(require, 'ddl')
 if not ok then
@@ -35,12 +34,9 @@ pgroup.before_all(function(g)
     t.assert_equals(type(result), 'table')
     t.assert_equals(err, nil)
 
-    helpers.call_on_storages(g.cluster, function(server)
-        server.net_box:eval([[
-            local storage_stat = require('test.helpers.storage_stat')
-            storage_stat.init_on_storage_for_select()
-        ]])
-    end)
+    g.cluster.main_server.net_box:eval([[
+        require('crud').cfg{ stats = true }
+    ]])
 end)
 
 pgroup.after_all(function(g) helpers.stop_cluster(g.cluster) end)
@@ -367,22 +363,19 @@ for name, case in pairs(cases) do
     pgroup[('test_%s_wont_lead_to_map_reduce'):format(name)] = function(g)
         case.prepare_data(g, case.space_name)
 
-        local stat_a = storage_stat.collect(g.cluster)
+        local router = g.cluster:server('router').net_box
+        local map_reduces_before = helpers.get_map_reduces_stat(router, case.space_name)
 
-        local result, err = g.cluster.main_server.net_box:call('crud.select', {
+        local result, err = router:call('crud.select', {
             case.space_name, case.conditions
         })
         t.assert_equals(err, nil)
         t.assert_not_equals(result, nil)
         t.assert_equals(#result.rows, 1)
 
-        local stat_b = storage_stat.collect(g.cluster)
-
-        -- Check a number of select() requests made by CRUD on cluster's storages
-        -- after calling select() on a router. Make sure only a single storage has
-        -- a single select() request. Otherwise we lead to map-reduce.
-        local stats = storage_stat.diff(stat_b, stat_a)
-        t.assert_equals(storage_stat.total(stats), 1, 'Select request was not a map reduce')
+        local map_reduces_after = helpers.get_map_reduces_stat(router, case.space_name)
+        local diff = map_reduces_after - map_reduces_before
+        t.assert_equals(diff, 0, 'Select request was not a map reduce')
     end
 end
 
@@ -390,22 +383,19 @@ pgroup.test_select_for_part_of_sharding_key_will_lead_to_map_reduce = function(g
     local space_name = 'customers_name_age_key_different_indexes'
     prepare_data_name_age_sharding_key(g, space_name)
 
-    local stat_a = storage_stat.collect(g.cluster)
+    local router = g.cluster:server('router').net_box
+    local map_reduces_before = helpers.get_map_reduces_stat(router, space_name)
 
-    local result, err = g.cluster.main_server.net_box:call('crud.select', {
+    local result, err = router:call('crud.select', {
         space_name, {{'==', 'age', 58}},
     })
     t.assert_equals(err, nil)
     t.assert_not_equals(result, nil)
     t.assert_equals(#result.rows, 1)
 
-    local stat_b = storage_stat.collect(g.cluster)
-
-    -- Check a number of select() requests made by CRUD on cluster's storages
-    -- after calling select() on a router. Make sure it was a map-reduce
-    -- since we do not have sharding key values in conditions.
-    local stats = storage_stat.diff(stat_b, stat_a)
-    t.assert_equals(storage_stat.total(stats), 2, 'Select request was a map reduce')
+    local map_reduces_after = helpers.get_map_reduces_stat(router, space_name)
+    local diff = map_reduces_after - map_reduces_before
+    t.assert_equals(diff, 1, 'Select request was a map reduce')
 end
 
 pgroup.test_select_secondary_idx = function(g)
diff --git a/test/integration/pairs_test.lua b/test/integration/pairs_test.lua
index aacb052f..a0c90618 100644
--- a/test/integration/pairs_test.lua
+++ b/test/integration/pairs_test.lua
@@ -5,7 +5,6 @@ local t = require('luatest')
 local crud_utils = require('crud.common.utils')
 
 local helpers = require('test.helper')
-local storage_stat = require('test.helpers.storage_stat')
 
 local pgroup = t.group('pairs', {
     {engine = 'memtx'},
@@ -27,12 +26,9 @@ pgroup.before_all(function(g)
 
     g.space_format = g.cluster.servers[2].net_box.space.customers:format()
 
-    helpers.call_on_storages(g.cluster, function(server)
-        server.net_box:eval([[
-            local storage_stat = require('test.helpers.storage_stat')
-            storage_stat.init_on_storage_for_select()
-        ]])
-    end)
+    g.cluster.main_server.net_box:eval([[
+        require('crud').cfg{ stats = true }
+    ]])
 end)
 
 pgroup.after_all(function(g) helpers.stop_cluster(g.cluster) end)
@@ -842,10 +838,11 @@ pgroup.test_pairs_no_map_reduce = function(g)
 
     table.sort(customers, function(obj1, obj2) return obj1.id < obj2.id end)
 
-    local stat_a = storage_stat.collect(g.cluster)
+    local router = g.cluster:server('router').net_box
+    local map_reduces_before = helpers.get_map_reduces_stat(router, 'customers')
 
     -- Case: no conditions, just bucket id.
-    local rows = g.cluster.main_server.net_box:eval([[
+    local rows = router:eval([[
         local crud = require('crud')
 
         return crud.pairs(...):totable()
@@ -858,15 +855,9 @@ pgroup.test_pairs_no_map_reduce = function(g)
         {3, 2804, 'David', 'Smith', 33, 'Los Angeles'},
     })
 
-    local stat_b = storage_stat.collect(g.cluster)
-    t.assert_equals(storage_stat.diff(stat_b, stat_a), {
-        ['s-1'] = {
-            requests = 1,
-        },
-        ['s-2'] = {
-            requests = 0,
-        },
-    })
+    local map_reduces_after_1 = helpers.get_map_reduces_stat(router, 'customers')
+    local diff_1 = map_reduces_after_1 - map_reduces_before
+    t.assert_equals(diff_1, 0, 'Select request was not a map reduce')
 
     -- Case: EQ on secondary index, which is not in the sharding
     -- index (primary index in the case).
@@ -883,13 +874,7 @@ pgroup.test_pairs_no_map_reduce = function(g)
         {4, 1161, 'William', 'White', 81, 'Chicago'},
     })
 
-    local stat_c = storage_stat.collect(g.cluster)
-    t.assert_equals(storage_stat.diff(stat_c, stat_b), {
-        ['s-1'] = {
-            requests = 0,
-        },
-        ['s-2'] = {
-            requests = 1,
-        },
-    })
+    local map_reduces_after_2 = helpers.get_map_reduces_stat(router, 'customers')
+    local diff_2 = map_reduces_after_2 - map_reduces_after_1
+    t.assert_equals(diff_2, 0, 'Select request was not a map reduce')
 end
diff --git a/test/integration/select_test.lua b/test/integration/select_test.lua
index f42896f3..97eadf35 100644
--- a/test/integration/select_test.lua
+++ b/test/integration/select_test.lua
@@ -6,7 +6,6 @@ local crud = require('crud')
 local crud_utils = require('crud.common.utils')
 
 local helpers = require('test.helper')
-local storage_stat = require('test.helpers.storage_stat')
 
 local pgroup = t.group('select', {
     {engine = 'memtx'},
@@ -28,12 +27,9 @@ pgroup.before_all(function(g)
 
     g.space_format = g.cluster.servers[2].net_box.space.customers:format()
 
-    helpers.call_on_storages(g.cluster, function(server)
-        server.net_box:eval([[
-            local storage_stat = require('test.helpers.storage_stat')
-            storage_stat.init_on_storage_for_select()
-        ]])
-    end)
+    g.cluster:server('router').net_box:eval([[
+        require('crud').cfg{ stats = true }
+    ]])
 end)
 
 pgroup.after_all(function(g) helpers.stop_cluster(g.cluster) end)
@@ -1624,7 +1620,8 @@ pgroup.test_select_no_map_reduce = function(g)
 
     table.sort(customers, function(obj1, obj2) return obj1.id < obj2.id end)
 
-    local stat_a = storage_stat.collect(g.cluster)
+    local router = g.cluster:server('router').net_box
+    local map_reduces_before = helpers.get_map_reduces_stat(router, 'customers')
 
     -- Case: no conditions, just bucket id.
     local result, err = g.cluster.main_server.net_box:call('crud.select', {
@@ -1637,15 +1634,9 @@ pgroup.test_select_no_map_reduce = function(g)
         {3, 2804, 'David', 'Smith', 33, 'Los Angeles'},
     })
 
-    local stat_b = storage_stat.collect(g.cluster)
-    t.assert_equals(storage_stat.diff(stat_b, stat_a), {
-        ['s-1'] = {
-            requests = 1,
-        },
-        ['s-2'] = {
-            requests = 0,
-        },
-    })
+    local map_reduces_after_1 = helpers.get_map_reduces_stat(router, 'customers')
+    local diff_1 = map_reduces_after_1 - map_reduces_before
+    t.assert_equals(diff_1, 0, 'Select request was not a map reduce')
 
     -- Case: EQ on secondary index, which is not in the sharding
     -- index (primary index in the case).
@@ -1659,13 +1650,7 @@ pgroup.test_select_no_map_reduce = function(g)
         {4, 1161, 'William', 'White', 81, 'Chicago'},
     })
 
-    local stat_c = storage_stat.collect(g.cluster)
-    t.assert_equals(storage_stat.diff(stat_c, stat_b), {
-        ['s-1'] = {
-            requests = 0,
-        },
-        ['s-2'] = {
-            requests = 1,
-        },
-    })
+    local map_reduces_after_2 = helpers.get_map_reduces_stat(router, 'customers')
+    local diff_2 = map_reduces_after_2 - map_reduces_after_1
+    t.assert_equals(diff_2, 0, 'Select request was not a map reduce')
 end