Manchester United lost 3-4 against Brentford, but more worryingly, center back Matthijs de Ligt's injury has once again raised red flags.

The Dutch defender had just returned from a foot injury and was replaced after only 35 minutes in the game, becoming a major concern for Manchester United before the crucial Europa League semi-final. De Ligt has not started since April 2 and only made a brief appearance as a substitute in the first leg of the last Europa League against Athletic Bilbao.

In this game, De Ligt had a long-awaited start, but he was injured in a collision with Brentford striker Brian Mbeumo and then fell to the ground. Brentford did not stop the attack and Kevin Shad scored.

In the post-match interview, Manchester United coach Ruben Amorim was asked about De Ligt's injury and replied: "We need to check further. I can only hope that this is just a minor problem. I am not only worried about the upcoming Europa League second leg, but also worried that this will affect our lineup planning for next season."

Manchester United is currently ranked 15th in the Premier League with 39 points. Although they will not face relegation, they have already missed out on qualifying for the European Cup next season. Therefore, the Europa League is Manchester United's last chance to qualify for the European Cup.

De Ligt was originally expected to provide Manchester United with defensive stability in the crucial stage of the European war. Now he is injured again, which will undoubtedly make the already injured Manchester United defense worse. With only a few days left before the second round of the Europa League against Athletic Bilbao, whether he can recover in time will have a significant impact on Manchester United's promotion.