Goals from Bruno Fernandes and Luke Shaw gave Manchester United a 2-0 derby victory at Manchester City to end the leaders' 15-match winning run in the Premier League.
Man Utd got off to a flying start and took the lead thanks to a second-minute penalty from Fernandes, awarded after Gabriel Jesus had fouled Anthony Martial.
At the other end, goalkeeper Dean Henderson denied Oleksandr Zinchenko and then tipped over a Kevin De Bruyne free-kick.
City continued to threaten after the break and Rodrigo's strike clipped the crossbar on 48 minutes.
Two minutes later, Shaw doubled Man Utd's lead. Following a driving run, he exchanged passes with Marcus Rashford, who later went off injured, before firing a low left-footed shot into the bottom corner.
Substitute Phil Foden and Raheem Sterling missed late chances for City, who remain top on 65 points.
Man Utd now move up to second place on 54 points.
Man City: 10 Mar v Southampton (H)
Man Utd: 14 Mar v West Ham (H)
Referee: Anthony Taylor. Assistants: Gary Beswick, Adam Nunn. Fourth official: Mike Dean. VAR: Paul Tierney. Assistant VAR: Harry Lennard.