diff --git a/spine-ts/core/src/Animation.ts b/spine-ts/core/src/Animation.ts
index e12ef090d..13bd0bdad 100644
--- a/spine-ts/core/src/Animation.ts
+++ b/spine-ts/core/src/Animation.ts
@@ -1455,7 +1455,7 @@ module spine {
 		}
 
 		setAttachment(skeleton: Skeleton, slot: Slot, attachmentName: string) {
-			slot.attachment = attachmentName == null ? null : skeleton.getAttachment(this.slotIndex, attachmentName);
+			slot.setAttachment(attachmentName == null ? null : skeleton.getAttachment(this.slotIndex, attachmentName));
 		}
 	}
 
diff --git a/spine-ts/core/src/AnimationState.ts b/spine-ts/core/src/AnimationState.ts
index 632c23278..fd4a6ce46 100644
--- a/spine-ts/core/src/AnimationState.ts
+++ b/spine-ts/core/src/AnimationState.ts
@@ -270,7 +270,7 @@ module spine {
 				var slot = slots[i];
 				if (slot.attachmentState == setupState) {
 					var attachmentName = slot.data.attachmentName;
-					slot.attachment = (attachmentName == null ? null : skeleton.getAttachment(slot.data.index, attachmentName));
+					slot.setAttachment(attachmentName == null ? null : skeleton.getAttachment(slot.data.index, attachmentName));
 				}
 			}
 			this.unkeyedState += 2; // Increasing after each use avoids the need to reset attachmentState for every slot.
@@ -390,7 +390,7 @@ module spine {
 		}
 
 		setAttachment (skeleton: Skeleton, slot: Slot, attachmentName: string, attachments: boolean) {
-			slot.attachment = attachmentName == null ? null : skeleton.getAttachment(slot.data.index, attachmentName);
+			slot.setAttachment(attachmentName == null ? null : skeleton.getAttachment(slot.data.index, attachmentName));
 			if (attachments) slot.attachmentState = this.unkeyedState + AnimationState.CURRENT;
 		}