The Red Devils secured a convincing 2-0 win over the Premier League leaders at Old Trafford as Jose Mourinho’s men blew the title race wide open.
Chelsea failed to click into gear and were largely outplayed as goals from Marcus Rashford and Ander Herrera secured the three points for the hosts.
The result allowed Tottenham to cut Chelsea’s lead at the top of the Premier League table down to four points to set up a thrilling conclusion to the season.
But Luiz was in no mood to make excuses after Sunday’s game, insisting that Manchester United were worthy winners.
Speaking to Chelsea’s website, Luiz said: “We lost because we did not play very well and it was not the Chelsea like before and sometimes this happens.
“We didn’t play well, Manchester United played better than us and they deserved to win.”
Chelsea, who finished 10th and without a trophy last season, must now dust themselves down as they prepare for their FA Cup semi-final showdown against Tottenham Hotspur at Wembley on Saturday evening.
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