diff --git a/CHANGELOG.md b/CHANGELOG.md
index 8b30e3dee..f097be0d6 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,10 @@
+## Unreleased
+
+### Bug Fixes
+
+- Also check stringified breadcrumbs key when reducing payload size [#1758](https://github.com/getsentry/sentry-ruby/pull/1758)
+  - Fixes [#1757](https://github.com/getsentry/sentry-ruby/issues/1757)
+
 ## 5.2.0
 
 ### Features
diff --git a/sentry-ruby/lib/sentry/transport.rb b/sentry-ruby/lib/sentry/transport.rb
index 8529e6db9..a63ff7c24 100644
--- a/sentry-ruby/lib/sentry/transport.rb
+++ b/sentry-ruby/lib/sentry/transport.rb
@@ -73,7 +73,12 @@ def serialize_envelope(envelope)
         result = item.to_s
 
         if result.bytesize > Event::MAX_SERIALIZED_PAYLOAD_SIZE
-          item.payload.delete(:breadcrumbs)
+          if item.payload.key?(:breadcrumbs)
+            item.payload.delete(:breadcrumbs)
+          elsif item.payload.key?("breadcrumbs")
+            item.payload.delete("breadcrumbs")
+          end
+
           result = item.to_s
         end
 
diff --git a/sentry-ruby/spec/sentry/transport_spec.rb b/sentry-ruby/spec/sentry/transport_spec.rb
index 443f7b983..7b038fd7f 100644
--- a/sentry-ruby/spec/sentry/transport_spec.rb
+++ b/sentry-ruby/spec/sentry/transport_spec.rb
@@ -201,7 +201,7 @@
         expect(serialized_result.bytesize).to be > Sentry::Event::MAX_SERIALIZED_PAYLOAD_SIZE
       end
 
-      it "sends the event and logs the action" do
+      it "deletes the event's breadcrumbs and sends it" do
         expect(subject).to receive(:send_data)
 
         subject.send_envelope(envelope)
@@ -209,6 +209,18 @@
         expect(io.string).to match(/Sending envelope with items \[event\]/)
       end
 
+      context "when the event hash has string keys" do
+        let(:envelope) { subject.envelope_from_event(event.to_json_compatible) }
+
+        it "deletes the event's breadcrumbs and sends it" do
+          expect(subject).to receive(:send_data)
+
+          subject.send_envelope(envelope)
+
+          expect(io.string).to match(/Sending envelope with items \[event\]/)
+        end
+      end
+
       context "if it's still oversized" do
         before do
           100.times do |i|