Manchester United were unable to maintain their winning start in the Premier League after losing 2-1 to Brighton and Hove Albion.
Erik ten Hag went with the same team that started the win over Fulham at Old Trafford, as match-winner Joshua Zirkzee and new signing Matthijs de Ligt kept their spots on the bench.
Amad Diallo had the Red Devils' first big chance after getting on the end of Diogo Dalot's well-weighted cross but the Ivorian winger scuffed his volley and failed to hit the target.
The opening goal arrived in the 32nd minute as former United striker Danny Welbeck bagged his 100th career goal with a close-range finish from Kaoru Mitoma's cross.
After United struggled to carve out chances, the visitors nearly fell further behind ten minutes after the break when Welbeck was close to getting a second but his header crashed against the crossbar.
Brighton were made to rue that miss on 60 minutes when Diallo restored parity with a deflected finish from close-range after being played through on goal by full-back Noussair Mazraoui.
The Red Devils had the ball in the back of the net after 72 minutes when Alejandro Garnacho appeared to have touched Zirkzee before going in, with VAR ruling out the goal after the latter was confirmed to have been offside.
With time running out, Brighton bagged the winning goal in the 95th minute after Simon Adingra did well to pick out Joao Pedro, who headed past Andre Onana from close rang.