diff --git a/main/src/main/scala/sbt/Defaults.scala b/main/src/main/scala/sbt/Defaults.scala
index 11b8b4726..866cfbf23 100755
--- a/main/src/main/scala/sbt/Defaults.scala
+++ b/main/src/main/scala/sbt/Defaults.scala
@@ -1413,6 +1413,14 @@ object Classpaths {
       val pluginIDs: Vector[ModuleID] = pluginJars.flatMap(_ get moduleID.key)
       GetClassifiersModule(pid, sbtDep +: pluginIDs, Vector(Configurations.Default), classifiers.toVector)
     }).value,
+    // Redefine scalaVersion and scalaBinaryVersion specifically for the dependency graph used for updateSbtClassifiers task.
+    // to fix https://github.com/sbt/sbt/issues/2686
+    scalaVersion := appConfiguration.value.provider.scalaProvider.version,
+    scalaBinaryVersion := binaryScalaVersion(scalaVersion.value),
+    ivyScala := {
+      Some(IvyScala(scalaVersion.value, scalaBinaryVersion.value, Vector(), checkExplicit = false, filterImplicit = false,
+        overrideScalaVersion = true).withScalaOrganization(scalaOrganization.value))
+    },
     updateSbtClassifiers in TaskGlobal := (Def.task {
       val s = streams.value
       val is = ivySbt.value
diff --git a/sbt/src/sbt-test/dependency-management/update-sbt-classifiers/build.sbt b/sbt/src/sbt-test/dependency-management/update-sbt-classifiers/build.sbt
new file mode 100644
index 000000000..77e00de55
--- /dev/null
+++ b/sbt/src/sbt-test/dependency-management/update-sbt-classifiers/build.sbt
@@ -0,0 +1 @@
+scalaVersion := "2.9.2"