Manchester City beat cross-town rivals United in their own back yard to go top of the Premier League.
But it came at a cost for Serbian defender Aleksandar Kolarov.
The left-back performed well as City took bragging rights in the derby with a 2-1 win but he came off the field missing a tooth.
City's back-up goalkeeper Willy Caballero shared a picture of the Serb's new-look smile alongside the caption: "Amazing game 2-1 against United at Old Trafford #cmoncity.