Arsenal missed the chance to open up a nine-point gap on Manchester City as they were held to a goalless draw against Nottingham Forest at the City Ground.
The Gunners were seeking to take advantage of second-placed City's defeat in the Manchester derby but could only add one point to their lead against their well-organised hosts.
Gabriel Martinelli missed their best chance of the first half when he fired wastefully wide from a few yards out and Forest needed Matz Sels to make an outstanding save from substitute Bukayo Saka's header to keep the Gunners out in the second period.
Arsenal's frustrations were compounded when an apparent handball in the Forest box by Ola Aina, as he attempted to prevent a corner in the 80th minute, went unpunished despite a VAR check.
According to the Premier League Match Centre, the officials "deemed the ball was played off Aina's shoulder first, while his arm was also in a "natural position".
Sean Dyche's side did not muster a shot on target during the game but they defended doggedly, helped by the outstanding Elliot Anderson, who marshalled the midfield impressively as the hosts withstood long periods of Arsenal pressure.
It was another frustrating outing for Arsenal following their goalless stalemate against Liverpool at the Emirates Stadium, when they also failed to fully capitalise on a Manchester City slip-up.
It is the first time that Arsenal have had consecutive goalless draws in the Premier League since the opening two games of the 2012/13 season against Sunderland and Stoke City.
Mikel Arteta's side still have a healthy seven-point cushion on Pep Guardiola's side, but will feel the margin should be greater. Forest, meanwhile, can celebrate a hard-earned point which keeps them five points clear of the relegation zone.
More to follow.
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