diff --git a/spring-context/src/main/java/org/springframework/format/annotation/DurationFormat.java b/spring-context/src/main/java/org/springframework/format/annotation/DurationFormat.java
index b6a8cdd450..05b69f7dd7 100644
--- a/spring-context/src/main/java/org/springframework/format/annotation/DurationFormat.java
+++ b/spring-context/src/main/java/org/springframework/format/annotation/DurationFormat.java
@@ -211,7 +211,7 @@ public @interface DurationFormat {
 					return candidate;
 				}
 			}
-			throw new IllegalArgumentException("No matching Unit for ChronoUnit: " + chronoUnit.name());
+			throw new IllegalArgumentException("No matching Unit for ChronoUnit." + chronoUnit.name());
 		}
 
 		/**