Arsenal lost 2-1 at home to Bournemouth, a result that gives Manchester City fresh hope in the Premier League title race.
Alex Scott scored the winner in the 74th minute, finishing calmly to seal a big victory for the visitors.
Arsenal remain nine points clear, but City have games in hand and can close the gap quickly.
Bournemouth took the lead in the 17th minute through Eli Junior Kroupi, who turned in a deflected cross. It was his 10th league goal this season.
Arsenal equalised before the break when Viktor Gyökeres scored from the penalty spot after a handball by Ryan Christie.
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But Arsenal struggled to take control.
Bournemouth stayed dangerous and got their reward when Scott reacted fastest in the box to score the winner past David Raya.
Arsenal pushed late but could not find a second goal, with Gyökeres missing a clear chance.
“A big punch in the face,” manager Mikel Arteta said after the match, apologising for the performance.