Leandro Trossard's first-half strike was cancelled out by Iliman Ndiaye's controversial penalty as Arsenal were held to a 1-1 draw at Everton on Saturday.
With Tuesday night's crucial Champions League quarter-final first leg against Real Madrid looming large, Mikel Arteta made five changes to the team that beat Fulham in midweek, with the likes of Martin Odegaard, Thomas Partey, Gabriel Martinelli and Bukayo Saka all left on the bench.
But in an open first half it was the much-changed visitors who broke the deadlock, with Trossard finishing well having been found by Raheem Sterling.
Saka and Martinelli were then introduced at half-time, only for Everton to level almost immediately through Ndiaye's spot-kick after Myles Lewis-Skelly was harshly adjudged to have pulled down Jack Harrison in the box, even though it was the Everton man who appeared to have fouled the Gunners teenager.
There were chances for Arsenal to still go on and win it, with Odegaard firing over before Jordan Pickford saved well from Martinelli and Merino headed wide from Kieran Tierney's cross. Liverpool will now have the opportunity to move 14 points clear at the top as the Gunners' fading title hopes suffered another blow.
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