diff --git a/src/animation/KeyframeTrack.js b/src/animation/KeyframeTrack.js
index da28822c463ef1870bd7945b6c2d8989bce38296..ab35d3bc9c70a7b51f72883886caf105b51fb25b 100644
--- a/src/animation/KeyframeTrack.js
+++ b/src/animation/KeyframeTrack.js
@@ -400,7 +400,7 @@ Object.assign( THREE.KeyframeTrack, {
 
 			var times = [], values = [];
 
-			THREE.AnimationUtils.flattenJSON( json, times, values, 'value' );
+			THREE.AnimationUtils.flattenJSON( json[ 'keys' ], times, values, 'value' );
 
 			json[ 'times' ] = times;
 			json[ 'values' ] = values;