Champions League: Mainoo, Shaw injury blow exposes Manchester United's biggest weakness before Atletico Madrid clash

Manchester United's injury concerns ahead of their UEFA Champions League (UCL) clash with Atletico Madrid go beyond losing two players. The bigger question for Michael Carrick is whether his side can cope without two footballers who offer different solutions to problems United could face in Madrid.

Kobbie Mainoo and Luke Shaw have been ruled out of the trip to the Metropolitano after suffering physical issues, according to Fabrizio Romano. Carrick confirmed their unavailability ahead of the encounter.

They're not available tomorrow, the United manager said. Their absence leaves Carrick with important decisions to make, particularly against an Atletico side known for making life difficult for opponents through aggressive pressing, tight defensive organisation and quick transitions.

Mainoo's absence could prove especially costly if United struggle to keep possession under pressure. The midfielder's ability to receive the ball in crowded areas, turn away from opponents and connect defence with attack offers United an important outlet when space is limited.

Without him, United risk becoming more predictable in possession, relying on safer passes or attempting to bypass Atletico's midfield altogether. That could leave their forwards isolated and invite further pressure on the defence.

Shaw's absence presents a different problem. Beyond his defensive responsibilities, the left-back offers an outlet down the flank and can help United build attacks from deeper positions.

His ability to move inside or overlap also gives the team options when opponents try to shut down their preferred passing routes. Losing both players therefore threatens more than United's starting XI.

It could affect how they progress the ball, escape pressure and create chances against an opponent unlikely to give them much time to settle. The concern for Carrick is how quickly those gaps could become connected.

If United struggle to retain possession without Mainoo, their defence may come under sustained pressure. If Shaw's absence also limits their options on the left, Atletico could find it easier to restrict United's attacking outlets and keep them pinned back.