Manchester City have been a thorn in Arsenal’s side in their quest for silverware.
In two of Arsenal's three second-placed finishes in the Premier League, the Gunners have been behind Pep Guardiola's side.
City beat Arsenal in the Carabao Cup final with one of their best performances of the season and that seems to have galvanised them.
They put four past Liverpool in the FA Cup to reach the semi-finals earlier on Saturday, before the Gunners lost at Southampton in their last-eight tie.
Arsenal have to travel to Etihad Stadium in April, which is likely to play a big part in this season's title race.
"It was only a couple of weeks ago people were saying Arsenal could do the quadruple. Now they are in two competitions," said former Manchester City and England defender Micah Richards.
"Man City, after what they did earlier on [beating Liverpool in the FA Cup], look like they are going to push them all the way for the league.
"The most disappointing thing for me was watching Arsenal and their attitude. They have been excellent defensively, in transitions they have been very good, the shape has been good and the effort has been as good as anyone.
"For them to turn up the way they did, I thought was very poor."
Arsenal will hope this blip is only a footnote in what can still be a successful season – but the Gunners are going to have get back to their best, and quickly.
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