Manchester United might be about to find out just how good Erik ten Hag is

For so long on Thursday night everything looked to be going smoothly for Manchester United and Erik ten Hag. An early 2-0 lead, attackers finding form, tactical changes working, it was shaping up to be a routine European night.

But rather than making short work of a two-legged tie, United now face a tricky second leg against Sevilla and a week that could define their season. As halves of football go, it was as bad as it gets.

Progress in the Europa League and the FA Cup is now on the line next week and United's place in the top four isn't yet secured. In fact, given they still have to play Tottenham, it's very much on the line. They could yet head to North London on Thursday, April 27 in fifth place.

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Ten Hag has enjoyed a hugely successful first season at Old Trafford and one trophy is already in the bag, but it does feel like the next week or so is when the very best managers truly prove their worth. It's not a week that will define Ten Hag at United, but it could be another chance to prove his own credentials.

The loss of Raphael Varane and Lisandro Martinez to injury on Thursday night, on top of the absence of Marcus Rashford, is disastrous. United also went from having a chance to finish the tie off to heading to Spain next week with it in the balance.

Ten Hag sounded the rallying cry at his press conference on Friday and he knows he needs his entire squad to step up now.

"Every game is a battle, every game is a fight and you have to be ready for that fight," he said.

"We have a squad - we have more than 11 starters - so now others are on and when their time is there you have to show and contribute to the team, you have to be ready. That is