Manchester United came from behind to overcome West Ham, with Jesse Lingard scoring a stunning late winner against his former club and David de Gea saving an injury-time penalty.
Lingard, who had a successful loan stint at London Stadium last season, came on as a second-half replacement and scored with two minutes left on his right foot into the top corner.
With four victories and a tie this season, Ole Gunnar Solskjaer's team stays undefeated in the league, while West Ham suffers their first defeat of the season.
Lingard said: "I got a brilliant reception. I had a good time here but I have to move on with Man United and do my best with Man United."
He later commented on his midweek blunder against Young Boys, saying: "Mistakes happen in football, you have to overcome those things."
Source: transfermarketweb.com