He was at fault for the goal twice, first he went high up the pitch to try and intercept the ball, missed it.
Then he ran back to the penalty box, just as Strootman was crossing it, he stopped still as Gervinho nipped in and around him to flick it in.
Shameful defending, not surprised though, Bonucci isn't a defender at the best of times, he's an Italian David Luiz