The Premier League leader Arsenal threw away a two-goal lead for the second league game in a row as their title chances took another hit in a 2-2 draw at West Ham.
Arsenal got off to the perfect start as Gabriel Jesus and Martin Odegaard put the Gunners two up after 10 minutes with clinical first-time finishes but just like last week at Anfield, Mikel Arteta's side could not hold on to their advantage.
They conceded just before half-time when Said Benrahma struck from the penalty spot after Gabriel fouled Lucas Paqueta before Arsenal were awarded a spot kick themselves just after half-time for Michail Antonio's handball, only for Bukayo Saka to uncharacteristically put his effort wide.
That proved even more costly when West Ham equalised two minutes later through Jarrod Bowen's smart finish.
Antonio hit the bar for the Hammers in the final 10 minutes but Arteta's Arsenal will rue another two points dropped.
The result means Arsenal are four points above second-placed Manchester City having played a game more. City's FA Cup semi-final next weekend means the Gunners can extend that gap to seven points if they beat Southampton on Friday Night Football.
After that, Arsenal travel to the Etihad Stadium to take on Pep Guardiola's side in a crucial game for the title race.