Arsenal beat Manchester United 2-0 on Thursday night to snap a four-game league winless streak and give Gunners boss Mikel Arteta his first victory.
Nicolas Pepe scored in the eighth minute while Sokratis Papastathopoulos struck in the 42nd minute to help the home side break a three-match losing streak at the Emirates on New Year's Day.
Former team captain Arteta returned to Arsenal to take over permanent managerial duties after Unai Emery was sacked in November. The London club struggled in December under interim boss Freddie Ljungberg before Arteta was hired.
Arsenal jump back into the top half of the Premier League table while the United, playing without Paul Pogba, remain in fifth place.