Bailly, not to be outdone, gave away a corner in the build-up to the second and then chopped down Gross in the box for Brighton's penalty just before half-time.
Goal! Lukaku pulls one back for United with a header!
He was left frustrated by United's performance on the south coast, which followed a win over Leicester last week and an encouraging week of training.
He picked Lindelof and Bailly against Brighton and after 45 minutes they had helped cost United three goals.
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The France global was handed a rare starting opportunity against Brighton as a result of Alexis Sanchez's injury but failed to seize the chance to impress.
Lindelof was at fault for the first, letting Murray steal in to score.
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The film which released on Independence Day has managed to collect Rs 33.25 crore in the first two days of its release. "The big Independence Day holiday results in big numbers at the box office", tweeted trade analyst Taran Adarsh.
But despite the former French World Cup winning captain becoming the bookies favourite to be the next Old Trafford boss a large part of the Old Trafford faithful have taken to Twitter to voice their support of their current coach.
Manchester United fans were definitely disappointed by the weak performance that was put in by the players vs Brighton.
Dale Stephens beat Fred to a loose ball in midfield and released Gross before the German was brought down by a lunge inside the area by the Ivorian.
But the damage had already been done as Brighton sat comfortably on their lead until virtually the last kick of the match.
United came back from two goals down to win twice last season and when Romelu Lukaku headed in his first goal of the season from close range it looked like it might be on again.
Guardiola's team were widely regarded as one of the finest sides to ever play in the English top-flight, 12 months after the Catalan coach played out his first and only trophyless season as a professional manager.
His time at Old Trafford threatens to go the same way, particularly with Tottenham next up a week on Monday.