diff --git a/spine-csharp/src/Animation.cs b/spine-csharp/src/Animation.cs
index 704fa5027..f0fe82916 100644
--- a/spine-csharp/src/Animation.cs
+++ b/spine-csharp/src/Animation.cs
@@ -1898,6 +1898,9 @@ namespace Spine {
 				return slotIndex;
 			}
 		}
+
+		/// <summary>The attachment for which the <see cref="SlotPose.SequenceIndex"/> will be set.</summary>
+		/// <seealso cref="Attachment.TimelineAttachment"/>.
 		public Attachment Attachment {
 			get {
 				return (Attachment)attachment;
@@ -1922,11 +1925,8 @@ namespace Spine {
 			SlotPose pose = appliedPose ? slot.applied : slot.pose;
 
 			Attachment slotAttachment = pose.attachment;
-			if (slotAttachment != attachment) {
-				IHasSequence sequenceAttachment = slotAttachment as IHasSequence;
-				if ((sequenceAttachment == null)
-					|| sequenceAttachment.TimelineAttachment != attachment) return;
-			}
+			IHasSequence hasSequence = slotAttachment as IHasSequence;
+			if ((hasSequence == null) || slotAttachment.TimelineAttachment != attachment) return;
 
 			if (direction == MixDirection.Out) {
 				if (blend == MixBlend.Setup) pose.SequenceIndex = -1;
@@ -1944,7 +1944,7 @@ namespace Spine {
 			int modeAndIndex = (int)frames[i + MODE];
 			float delay = frames[i + DELAY];
 
-			int index = modeAndIndex >> 4, count = (((IHasSequence)slotAttachment).Sequence).Regions.Length;
+			int index = modeAndIndex >> 4, count = hasSequence.Sequence.Regions.Length;
 			SequenceMode mode = (SequenceMode)(modeAndIndex & 0xf);
 			if (mode != SequenceMode.Hold) {
 				index += (int)((time - before) / delay + 0.0001f);
diff --git a/spine-csharp/src/Attachments/Attachment.cs b/spine-csharp/src/Attachments/Attachment.cs
index cb4467e0d..ea7c694e3 100644
--- a/spine-csharp/src/Attachments/Attachment.cs
+++ b/spine-csharp/src/Attachments/Attachment.cs
@@ -33,17 +33,25 @@ namespace Spine {
 
 	/// <summary>The base class for all attachments.</summary>
 	abstract public class Attachment {
+		internal Attachment timelineAttachment;
+
 		/// <summary>The attachment's name.</summary>
 		public string Name { get; }
 
+		/// <summary>Timelines for the timeline attachment are also applied to this attachment.
+		/// May be null if no attachment-specific timelines should be applied.</summary>
+		public Attachment TimelineAttachment { get { return timelineAttachment; } set { timelineAttachment = value; } }
+
 		protected Attachment (string name) {
 			if (name == null) throw new ArgumentNullException("name", "name cannot be null");
 			this.Name = name;
+			timelineAttachment = this;
 		}
 
 		/// <summary>Copy constructor.</summary>
 		protected Attachment (Attachment other) {
 			Name = other.Name;
+			timelineAttachment = other.timelineAttachment;
 		}
 
 		override public string ToString () {
diff --git a/spine-csharp/src/Attachments/IHasSequence.cs b/spine-csharp/src/Attachments/IHasSequence.cs
index 74ec9acbd..15da803ca 100644
--- a/spine-csharp/src/Attachments/IHasSequence.cs
+++ b/spine-csharp/src/Attachments/IHasSequence.cs
@@ -42,9 +42,6 @@ namespace Spine {
 		void SetColor (Color32F color);
 		void SetColor (float r, float g, float b, float a);
 		Sequence Sequence { get; }
-		/// <summary>Timelines for the timeline attachment are also applied to this attachment.
-		/// May be null if no attachment-specific timelines should be applied.</summary>
-		Attachment TimelineAttachment { get; set; }
 		void UpdateSequence ();
 	}
 }
diff --git a/spine-csharp/src/Attachments/MeshAttachment.cs b/spine-csharp/src/Attachments/MeshAttachment.cs
index a5800d830..74e21764b 100644
--- a/spine-csharp/src/Attachments/MeshAttachment.cs
+++ b/spine-csharp/src/Attachments/MeshAttachment.cs
@@ -73,11 +73,7 @@ namespace Spine {
 
 		public string Path { get { return path; } set { path = value; } }
 		public Sequence Sequence { get { return sequence; } }
-		Attachment IHasSequence.TimelineAttachment {
-			get { return timelineAttachment; }
-			set { timelineAttachment = (VertexAttachment)value; }
-		}
-
+		
 		public MeshAttachment ParentMesh {
 			get { return parentMesh; }
 			set {
diff --git a/spine-csharp/src/Attachments/RegionAttachment.cs b/spine-csharp/src/Attachments/RegionAttachment.cs
index 654ea8018..2154f7912 100644
--- a/spine-csharp/src/Attachments/RegionAttachment.cs
+++ b/spine-csharp/src/Attachments/RegionAttachment.cs
@@ -46,7 +46,6 @@ namespace Spine {
 		public const int BRX = 6, BRY = 7;
 
 		internal readonly Sequence sequence;
-		internal Attachment timelineAttachment;
 		internal float x, y, rotation, scaleX = 1, scaleY = 1, width, height;
 		// Color is a struct, set to protected to prevent
 		// Color color = slot.color; color.a = 0.5;
@@ -76,13 +75,11 @@ namespace Spine {
 
 		public string Path { get; set; }
 		public Sequence Sequence { get { return sequence; } }
-		public Attachment TimelineAttachment { get { return timelineAttachment; } set { timelineAttachment = value; } }
-
+		
 		public RegionAttachment (string name, Sequence sequence)
 			: base(name) {
 			if (sequence == null) throw new ArgumentException("sequence cannot be null.", "sequence");
 			this.sequence = sequence;
-			timelineAttachment = this;
 		}
 
 		/// <summary>Copy constructor.</summary>
@@ -98,7 +95,6 @@ namespace Spine {
 			height = other.height;
 			color = other.color;
 			sequence = new Sequence(other.sequence);
-			timelineAttachment = other.timelineAttachment;
 		}
 
 		/// <summary><para>
diff --git a/spine-csharp/src/Attachments/VertexAttachment.cs b/spine-csharp/src/Attachments/VertexAttachment.cs
index 29ff3b40c..f9e701d4d 100644
--- a/spine-csharp/src/Attachments/VertexAttachment.cs
+++ b/spine-csharp/src/Attachments/VertexAttachment.cs
@@ -37,7 +37,6 @@ namespace Spine {
 		static readonly Object nextIdLock = new Object();
 
 		internal readonly int id;
-		internal VertexAttachment timelineAttachment;
 		internal int[] bones;
 		internal float[] vertices;
 		internal int worldVerticesLength;
@@ -47,17 +46,13 @@ namespace Spine {
 		public int[] Bones { get { return bones; } set { bones = value; } }
 		public float[] Vertices { get { return vertices; } set { vertices = value; } }
 		public int WorldVerticesLength { get { return worldVerticesLength; } set { worldVerticesLength = value; } }
-		/// <summary>Timelines for the timeline attachment are also applied to this attachment.
-		/// May be null if no attachment-specific timelines should be applied.</summary>
-		public VertexAttachment TimelineAttachment { get { return timelineAttachment; } set { timelineAttachment = value; } }
-
+		
 		public VertexAttachment (string name)
 			: base(name) {
 
 			lock (VertexAttachment.nextIdLock) {
 				id = VertexAttachment.nextID++;
 			}
-			timelineAttachment = this;
 		}
 
 		/// <summary>Copy constructor.</summary>