Hector Bellerin came to Arsenal's rescue in stoppage time to clinch a 2-2 draw against Chelsea after conceding in an absorbing Premier League encounter on Wednesday.
All four goals came in the final half hour of a game that left third-place and defending champion Chelsea 16 points behind Manchester City and Arsenal 23 adrift of the leaders.
The deficit would have been even worse for the sixth-place hosts had Bellerin not redeemed himself. The right back's challenge on Eden Hazard had allowed the Chelsea winger to cancel out Jack Wilshere's opener in the 67th minute.
Marcos Alonso fired Chelsea in front in the 84th with his sixth goal of the season, but wasn't as meticulous back on defensive duties in the second minute of stoppage time. A headed clearance went straight to Bellerin, who leveled with a half-volley.
Chelsea was still pursuing the winner in the third minute of stoppage time when defender Davide Zappacosta struck the crossbar.
Had striker Alvaro Morata not missed so many chances this could have been a third consecutive win for Chelsea.
Chelsea is becoming reliant on Alonso for goals, with the left-sided defender the team's second-highest scorer behind Morata.