Manchester City manager Pep Guardiola was left to rue his side's frailty from set-pieces after Manchester United came from two goals down to snatch a dramatic 3-2 win at the Etihad Stadium on Sunday.
Guardiola's men appeared on course to be crowned Premier League champions with a record six games to spare when they eased into a 2-0 half-time lead through Vincent Kompany and Ilkay Gundogan.
United stormed back in the second half, though, as a Paul Pogba brace pulled them level and then an unmarked Chris Smalling volleyed in from a free-kick to spoil City's title party.
"We have to be better and more focused on set-pieces," Guardiola told Sky Sports .
"Our team tried to create and attack, that is what we have done all season, we tried to produce all of that quality and goals. You have to defend a little better in the second half, but it is football."
Guardiola's attention will now turn to picking his players up for Tuesday's Champions League quarter-final second leg against Liverpool, where they are faced with the daunting task of overturning a three-goal deficit.
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"We will try to pick ourselves up for Liverpool, we are professionals," he told BBC Radio 5 live .
"We were not good enough in the end. The schedule is like this, that's why this competition is so tough."