diff --git a/src/cli/rustup_mode.rs b/src/cli/rustup_mode.rs
index 4e26f191952..b86185a6a1b 100644
--- a/src/cli/rustup_mode.rs
+++ b/src/cli/rustup_mode.rs
@@ -319,6 +319,12 @@ pub fn cli() -> App<'static, 'static> {
                                 .help("Force an update, even if some components are missing")
                                 .long("force")
                                 .takes_value(false),
+                        )
+                        .arg(
+                            Arg::with_name("allow-downgrade")
+                                .help("Installs the most recent toolchain which supports all required components, even than this is older than the currently installed toolchain")
+                                .long("allow-downgrade")
+                                .takes_value(false),
                         ),
                 )
                 .subcommand(
@@ -819,7 +825,12 @@ fn update(cfg: &mut Cfg, m: &ArgMatches<'_>) -> Result<()> {
                     .values_of("targets")
                     .map(|v| v.collect())
                     .unwrap_or_else(Vec::new);
-                Some(toolchain.install_from_dist(m.is_present("force"), &components, &targets)?)
+                Some(toolchain.install_from_dist(
+                    m.is_present("force"),
+                    m.is_present("allow-downgrade"),
+                    &components,
+                    &targets,
+                )?)
             } else if !toolchain.exists() {
                 return Err(ErrorKind::InvalidToolchainName(toolchain.name().to_string()).into());
             } else {
diff --git a/src/cli/self_update.rs b/src/cli/self_update.rs
index cdb7bd12a6e..7b8173d917f 100644
--- a/src/cli/self_update.rs
+++ b/src/cli/self_update.rs
@@ -782,7 +782,7 @@ fn maybe_install_rust(
         println!();
     } else if cfg.find_default()?.is_none() {
         let toolchain = cfg.get_toolchain(toolchain_str, false)?;
-        let status = toolchain.install_from_dist(true, components, targets)?;
+        let status = toolchain.install_from_dist(true, false, components, targets)?;
         cfg.set_default(toolchain_str)?;
         println!();
         common::show_channel_update(&cfg, toolchain_str, Ok(status))?;
diff --git a/src/config.rs b/src/config.rs
index 9d6ad5d59bf..88aa367fb40 100644
--- a/src/config.rs
+++ b/src/config.rs
@@ -438,7 +438,7 @@ impl Cfg {
                             ErrorKind::OverrideToolchainNotInstalled(name.to_string())
                         })
                     } else {
-                        toolchain.install_from_dist(true, &[], &[])?;
+                        toolchain.install_from_dist(true, false, &[], &[])?;
                         Ok(Some((toolchain, reason)))
                     }
                 }
@@ -547,7 +547,7 @@ impl Cfg {
         // Update toolchains and collect the results
         let channels = channels.map(|(n, t)| {
             let t = t.and_then(|t| {
-                let t = t.install_from_dist(force_update, &[], &[]);
+                let t = t.install_from_dist(force_update, false, &[], &[]);
                 if let Err(ref e) = t {
                     (self.notify_handler)(Notification::NonFatalError(e));
                 }
@@ -599,7 +599,7 @@ impl Cfg {
     ) -> Result<Command> {
         let toolchain = self.get_toolchain(toolchain, false)?;
         if install_if_missing && !toolchain.exists() {
-            toolchain.install_from_dist(true, &[], &[])?;
+            toolchain.install_from_dist(true, false, &[], &[])?;
         }
 
         if let Some(cmd) = self.maybe_do_cargo_fallback(&toolchain, binary)? {
diff --git a/src/dist/dist.rs b/src/dist/dist.rs
index a9d241bcf0d..d8dc1f8c77e 100644
--- a/src/dist/dist.rs
+++ b/src/dist/dist.rs
@@ -580,6 +580,7 @@ pub fn update_from_dist<'a>(
     profile: Option<Profile>,
     prefix: &InstallPrefix,
     force_update: bool,
+    allow_downgrade: bool,
     old_date: Option<&str>,
     components: &[&str],
     targets: &[&str],
@@ -601,6 +602,7 @@ pub fn update_from_dist<'a>(
         profile,
         prefix,
         force_update,
+        allow_downgrade,
         old_date,
         components,
         targets,
@@ -622,6 +624,7 @@ fn update_from_dist_<'a>(
     profile: Option<Profile>,
     prefix: &InstallPrefix,
     force_update: bool,
+    allow_downgrade: bool,
     old_date: Option<&str>,
     components: &[&str],
     targets: &[&str],
@@ -644,7 +647,8 @@ fn update_from_dist_<'a>(
         Some(if provided < 1 { 1 } else { provided })
     };
 
-    // We never want to backtrack further back than the nightly that's already installed.
+    // In case there is no allow-downgrade option set
+    // we never want to backtrack further back than the nightly that's already installed.
     //
     // If no nightly is installed, it makes no sense to backtrack beyond the first ever manifest,
     // which is 2014-12-20 according to
@@ -652,13 +656,12 @@ fn update_from_dist_<'a>(
     //
     // We could arguably use the date of the first rustup release here, but that would break a
     // bunch of the tests, which (inexplicably) use 2015-01-01 as their manifest dates.
-    let first_manifest = old_date
-        .map(|date| {
-            Utc.from_utc_date(
-                &NaiveDate::parse_from_str(date, "%Y-%m-%d").expect("Malformed manifest date"),
-            )
-        })
-        .unwrap_or_else(|| Utc.from_utc_date(&NaiveDate::from_ymd(2014, 12, 20)));
+    let first_manifest = Utc.from_utc_date(&NaiveDate::from_ymd(2014, 12, 20));
+    let old_manifest = if allow_downgrade || old_date == None {
+        first_manifest
+    } else {
+        utc_from_manifest_date(old_date.unwrap())
+    };
 
     loop {
         match try_update_from_dist_(
@@ -713,22 +716,10 @@ fn update_from_dist_<'a>(
                 // the components that the user currently has installed. Let's try the previous
                 // nightlies in reverse chronological order until we find a nightly that does,
                 // starting at one date earlier than the current manifest's date.
-                let try_next = Utc
-                    .from_utc_date(
-                        &NaiveDate::parse_from_str(
-                            toolchain.date.as_ref().unwrap_or(&fetched),
-                            "%Y-%m-%d",
-                        )
-                        .unwrap_or_else(|_| {
-                            panic!(
-                                "Malformed manifest date: {:?}",
-                                toolchain.date.as_ref().unwrap_or(&fetched)
-                            )
-                        }),
-                    )
-                    .pred();
-
-                if try_next < first_manifest {
+                let toolchain_date = toolchain.date.as_ref().unwrap_or(&fetched);
+                let try_next = utc_from_manifest_date(toolchain_date).pred();
+
+                if try_next < old_manifest {
                     // Wouldn't be an update if we go further back than the user's current nightly.
                     if let Some(e) = first_err {
                         break Err(e);
@@ -926,3 +917,9 @@ fn dl_v1_manifest<'a>(download: DownloadCfg<'a>, toolchain: &ToolchainDesc) -> R
 
     Ok(urls)
 }
+
+fn utc_from_manifest_date(date_str: &str) -> Date<Utc> {
+    let msg = format!("Malformed manifest date: {:?}", date_str);
+    let date = NaiveDate::parse_from_str(date_str, "%Y-%m-%d").expect(&msg);
+    Utc.from_utc_date(&date)
+}
diff --git a/src/install.rs b/src/install.rs
index 1d6eadd84e4..cbdd36f8252 100644
--- a/src/install.rs
+++ b/src/install.rs
@@ -24,6 +24,8 @@ pub enum InstallMethod<'a> {
         DownloadCfg<'a>,
         // --force
         bool,
+        // --allow-downgrade
+        bool,
         // toolchain already exists
         bool,
         // currently installed date
@@ -66,6 +68,7 @@ impl<'a> InstallMethod<'a> {
                 update_hash,
                 dl_cfg,
                 force_update,
+                allow_downgrade,
                 exists,
                 old_date,
                 components,
@@ -79,6 +82,7 @@ impl<'a> InstallMethod<'a> {
                     if exists { None } else { Some(profile) },
                     prefix,
                     force_update,
+                    allow_downgrade,
                     old_date,
                     components,
                     targets,
diff --git a/src/toolchain.rs b/src/toolchain.rs
index b0780e90691..8556c84f022 100644
--- a/src/toolchain.rs
+++ b/src/toolchain.rs
@@ -166,6 +166,7 @@ impl<'a> Toolchain<'a> {
     pub fn install_from_dist(
         &self,
         force_update: bool,
+        allow_downgrade: bool,
         components: &[&str],
         targets: &[&str],
     ) -> Result<UpdateStatus> {
@@ -177,6 +178,7 @@ impl<'a> Toolchain<'a> {
             update_hash.as_ref().map(|p| &**p),
             self.download_cfg(),
             force_update,
+            allow_downgrade,
             self.exists(),
             old_date.as_ref().map(|s| &**s),
             components,
@@ -193,6 +195,7 @@ impl<'a> Toolchain<'a> {
             self.download_cfg(),
             false,
             false,
+            false,
             None,
             &[],
             &[],
diff --git a/tests/cli-v2.rs b/tests/cli-v2.rs
index 9f412672154..25b22ae51d9 100644
--- a/tests/cli-v2.rs
+++ b/tests/cli-v2.rs
@@ -1374,3 +1374,71 @@ fn check_pgp_keys() {
         );
     })
 }
+
+#[test]
+fn install_fails_on_missing_component() {
+    clitools::setup(Scenario::MissingComponent, &|config| {
+        let trip = TargetTriple::from_build();
+        let expected = format!(
+            "component 'rls' for target '{}' is unavailable for download for channel nightly",
+            trip,
+        );
+
+        // this dist has no rls and there is no newer one
+        set_current_dist_date(config, "2019-09-14");
+        expect_ok(
+            config,
+            &[
+                "rustup",
+                "toolchain",
+                "install",
+                "nightly",
+                "--no-self-update",
+            ],
+        );
+        expect_err(
+            config,
+            &[
+                "rustup",
+                "toolchain",
+                "install",
+                "nightly",
+                "--no-self-update",
+                "-c",
+                "rls",
+            ],
+            &expected,
+        );
+    });
+}
+
+#[test]
+fn install_allow_downgrade() {
+    clitools::setup(Scenario::MissingComponent, &|config| {
+        // this dist has no rls, but rls is available on 2019-09-13
+        set_current_dist_date(config, "2019-09-14");
+        expect_ok(
+            config,
+            &[
+                "rustup",
+                "toolchain",
+                "install",
+                "nightly",
+                "--no-self-update",
+            ],
+        );
+        expect_ok(
+            config,
+            &[
+                "rustup",
+                "toolchain",
+                "install",
+                "nightly",
+                "--no-self-update",
+                "-c",
+                "rls",
+                "--allow-downgrade",
+            ],
+        );
+    });
+}