diff --git a/src/main/java/org/springframework/data/convert/CustomConversions.java b/src/main/java/org/springframework/data/convert/CustomConversions.java
index fdf7ced74..652dce516 100644
--- a/src/main/java/org/springframework/data/convert/CustomConversions.java
+++ b/src/main/java/org/springframework/data/convert/CustomConversions.java
@@ -372,7 +372,7 @@ public class CustomConversions {
 		 */
 		public Optional<Class<?>> computeIfAbsent(Class<?> sourceType,
 				Function<ConvertiblePair, Optional<Class<?>>> mappingFunction) {
-			return computeIfAbsent(sourceType, Object.class, mappingFunction);
+			return computeIfAbsent(sourceType, AbsentTargetTypeMarker.class, mappingFunction);
 		}
 
 		/**
@@ -391,6 +391,11 @@ public class CustomConversions {
 			TargetTypes targetTypes = customReadTargetTypes.computeIfAbsent(sourceType, TargetTypes::new);
 			return targetTypes.computeIfAbsent(targetType, mappingFunction);
 		}
+
+		/**
+		 * Marker type for absent target type caching.
+		 */
+		interface AbsentTargetTypeMarker {}
 	}
 
 	/**
diff --git a/src/test/java/org/springframework/data/convert/CustomConversionsUnitTests.java b/src/test/java/org/springframework/data/convert/CustomConversionsUnitTests.java
index 6bb6788c0..f5dcf244d 100644
--- a/src/test/java/org/springframework/data/convert/CustomConversionsUnitTests.java
+++ b/src/test/java/org/springframework/data/convert/CustomConversionsUnitTests.java
@@ -44,6 +44,7 @@ import org.threeten.bp.LocalDateTime;
  *
  * @author Oliver Gierke
  * @author Christoph Strobl
+ * @author Mark Paluch
  * @since 2.0
  */
 public class CustomConversionsUnitTests {
@@ -71,6 +72,17 @@ public class CustomConversionsUnitTests {
 		assertThat(conversions.hasCustomReadTarget(String.class, Long.class)).isTrue();
 	}
 
+	@Test // DATACMNS-1101
+	public void considersSubtypeCachingCorrectly() {
+
+		CustomConversions conversions = new CustomConversions(StoreConversions.NONE,
+				Arrays.asList(NumberToStringConverter.INSTANCE, StringToNumberConverter.INSTANCE));
+
+		assertThat(conversions.getCustomWriteTarget(Long.class, Object.class)).isEmpty();
+		assertThat(conversions.getCustomWriteTarget(Long.class)).hasValue(String.class);
+		assertThat(conversions.getCustomWriteTarget(Long.class, Object.class)).isEmpty();
+	}
+
 	@Test // DATACMNS-1035
 	public void populatesConversionServiceCorrectly() {