He's just rusty because Mancini wastes him as a defensive midfield blocker.
The MOTD commentator called Clark's tackle 'brave'. Also, have to mention Brav Guzan, almost getting his hand kicked off to gather the ball when the Sunderland player was offside anyway.
And Gabby taking a hit on his leg to score, SCARED COWARD SUNDERLAND can't handle that kind of stuff. :mon