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What once looked like a dream day ended in heartbreak for Union Berlin, who conceded a last-gasp goal to lose 3-2 to SC Braga in their first UEFA Champions League home match.

Braga's game-winning goal came in the fourth minute of stoppage time courtesy of Andre Castro. After a smartly played team sequence, Bruma played a short pass to Castro, who took a powerful strike from outside the box and sent it into the back of the net.

Union got off to a fast start and took a 2-0 lead by the 37th minute, with Sheraldo Becker scoring the club's first two Champions League goals in the process. Braga quickly began to mount a comeback and scored their first goal in the 41st minute through Sikou Niakate. Six minutes into the second half, the visitors were level thanks to a goal from Bruma, and after a lengthy stretch where both teams had their chances, Braga notched the dramatic winner in stoppage time.

The German side might be new to the Champions League, but conceding a stoppage time winner is becoming a familiar habit. In matchday one, Union were scoreless against Real Madrid until Jude Bellingham scored for the Spanish giants at the same exact time Castro did on Tuesday -- in the 94th minute.

Braga picked up their first win of the Champions League group stage and sit third in Group C tied on points with Real Madrid and Napoli. Union, meanwhile, are bottom with zero points.