Erik ten Hag was unhappy with one element of Manchester United’s win (Photo by DARREN STAPLES/AFP via Getty Images)

Erik ten Hag sent a warning to his Manchester United squad after criticising one element of his side’s Carabao Cup semi-final first leg win against Nottingham Forest.

The Red Devils must avoid a miracle comeback from Forest in the second leg at Old Trafford next week to progress to the Wembley final, where they’ll play either Newcastle United or Southampton.

United took the lead early on through Marcus Rashford at the Forest Ground and Wout Weghorst scored a second just before half-time, before Bruno Fernandes rounded off the victory late on.

However, despite their dominant start, United allowed Forest back into the tie and the home side had a goal chalked off after VAR showed Sam Surridge was offside.

It came after Forest moved out of their midfield diamond shape and found a foothold in the game, with United weathering a storm of around ten to fifteen minutes of home pressure.

While United came through the spell, Ten Hag has seen his side concede late on against Crystal Palace and Arsenal in the last fortnight.

And while Ten Hag was happy with his side’s overall performance, he says they must ‘learn’ and ‘improve’ to avoid allowing opponents back into matches.

United have a commanding lead going into the second leg (Photo by Matthew Peters/Manchester United via Getty Images)

‘There was one moment that could have changed the game and that is what we have to be aware of,’ said Ten Hag.

‘We have to improve but overall I think it was a good performance from our team but the first leg is done, one leg to go.

‘I have to say, we still didn’t react to counter-attacks. We knew that before and that can’t happen.

‘It’s still a moment where we have to learn and improve as a team. If we want to be top, we can’t be doing that.”

‘Don’t light the fire, we almost let them come into the game.

‘We can’t let an opponent come back into the game. We started so well, we had so much control and then in one moment everything can change.

‘We have to avoid that, we cannot allow opponents to come back into the game.’

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A perfectionist…