diff --git a/lm-core/src/main/scala/sbt/internal/librarymanagement/cross/CrossVersionUtil.scala b/lm-core/src/main/scala/sbt/internal/librarymanagement/cross/CrossVersionUtil.scala
index 4d2471136..50fcfd632 100644
--- a/lm-core/src/main/scala/sbt/internal/librarymanagement/cross/CrossVersionUtil.scala
+++ b/lm-core/src/main/scala/sbt/internal/librarymanagement/cross/CrossVersionUtil.scala
@@ -24,6 +24,7 @@ object CrossVersionUtil {
   private val basicVersion = raw"""($longPattern)\.($longPattern)\.($longPattern)"""
   private val tagPattern = raw"""(?:\w+(?:\.\w+)*)"""
   private val ReleaseV = raw"""$basicVersion(-\d+)?""".r
+  private val MajorV = raw"""($longPattern)""".r
   private[sbt] val BinCompatV = raw"""$basicVersion(-$tagPattern)?-bin(-.*)?""".r
   private val CandidateV = raw"""$basicVersion(-RC\d+)""".r
   private val NonReleaseV_n =
@@ -72,6 +73,7 @@ object CrossVersionUtil {
   private[sbt] def partialVersion(s: String): Option[(Long, Long)] =
     s match {
       case PartialVersion(major, minor) => Some((major.toLong, minor.toLong))
+      case MajorV(major)                => Some((major.toLong, 0L))
       case _                            => None
     }
 
diff --git a/lm-core/src/test/scala/sbt/librarymanagement/CrossVersionTest.scala b/lm-core/src/test/scala/sbt/librarymanagement/CrossVersionTest.scala
index 9ff2aa063..374982858 100644
--- a/lm-core/src/test/scala/sbt/librarymanagement/CrossVersionTest.scala
+++ b/lm-core/src/test/scala/sbt/librarymanagement/CrossVersionTest.scala
@@ -56,7 +56,12 @@ class CrossVersionTest extends UnitSpec {
   it should "for 2.0.0 return Some((2, 0))" in {
     sbtApiVersion("2.0.0") shouldBe Some((2, 0))
   }
-
+  "partialVersion" should "return None for xyz" in {
+    assert(partialVersion("xyz") == None)
+  }
+  it should "return 2 for 2" in {
+    assert(partialVersion("2") == Some((2, 0)))
+  }
   "isSbtApiCompatible" should "for 0.12.0-M1 return false" in {
     isSbtApiCompatible("0.12.0-M1") shouldBe false
   }
@@ -106,6 +111,9 @@ class CrossVersionTest extends UnitSpec {
   it should "for 2.0.0-RC1 return 2" in {
     binarySbtVersion("2.0.0-RC1") shouldBe "2"
   }
+  it should "for 2 return 2" in {
+    binarySbtVersion("2") shouldBe "2"
+  }
   it should "for 2.1.0-M1 return 2" in {
     binarySbtVersion("2.1.0-M1") shouldBe "2"
   }