diff --git a/compiler/resolution/src/org/jetbrains/kotlin/resolve/calls/inference/components/ConstraintInjector.kt b/compiler/resolution/src/org/jetbrains/kotlin/resolve/calls/inference/components/ConstraintInjector.kt
index cc931fb460f..fe96adf62e1 100644
--- a/compiler/resolution/src/org/jetbrains/kotlin/resolve/calls/inference/components/ConstraintInjector.kt
+++ b/compiler/resolution/src/org/jetbrains/kotlin/resolve/calls/inference/components/ConstraintInjector.kt
@@ -31,7 +31,7 @@ import org.jetbrains.kotlin.types.typeUtil.isNullableAny
 import java.util.*
 
 class ConstraintInjector(val constraintIncorporator: ConstraintIncorporator, val typeApproximator: TypeApproximator) {
-    private val ALLOWED_DEPTH_DELTA_FOR_INCORPORATION = 3
+    private val ALLOWED_DEPTH_DELTA_FOR_INCORPORATION = 1
 
     interface Context {
         val allTypeVariables: Map<TypeConstructor, NewTypeVariable>