Manchester United's poor run of results continued as they fell to a Champions League defeat by Atletico Madrid after conceding inside the first minute.
Although head coach Michael Carrick could reflect on a much-improved performance after making five changes to his starting line-up, United have now gone five games without a win.
The visitors never recovered after Alex Baena raced beyond Diogo Dalot on to a routine ball over the United defence, before squaring for the excellent Pablo Barrios, whose shot squirmed under Ayden Heaven and into the net.
Bryan Mbeumo wasted two good chances to level before the break while Marcus Rashford failed to make contact with Lisandro Martinez's pass.
After the interval, skipper Bruno Fernandes came closest when he lifted Youri Tielemans' lofted pass over Atletico keeper Jan Oblak but it dropped off target.
The hosts did have chances themselves, with Alejandro Grimaldo clipping a free-kick against the post before Julian Alvarez, making his second start of the season, failed to make the most of an opportunity created by Barrios.
United's final hope of an equaliser disappeared when Leny Yoro was sent off for tangling with substitute Jonathan David when the France defender was the last man.
Former Everton striker Ademola Lookman sealed the hosts' victory in the 79th minute as United became the first English side to lose in the Champions League this season.