Louis van Gaal revealed Luke Shaw was reduced to tears in the dressing room after suffering an "awful" broken leg during Manchester United's 2-1 Champions League loss to PSV Eindhoven.
The 20-year-old was on the receiving end of a thumping tackle from Hector Moreno early in the Group B clash, subsequently receiving seven minutes of treatment before being withdrawn on a stretcher while wearing an oxygen mask.
United confirmed the worst fears after the encounter, revealing Shaw would return to England for an operation having sustained a double fracture.
That news comes as a significant blow to the club and Van Gaal, who said on the BBC Sport website: "It is awful. The boy is in his second season and he has been playing fantastic. And now this happens.
"Shaw had an oxygen mask on and was crying in the dressing room. I hope he can play again this season.
"He is in hospital, he will be transferred with us, maybe, otherwise a day later and shall be operated in Manchester probably. It is awful."
Moreno went unpunished despite many deeming the challenge worthy of a red card and a penalty.
Van Gaal added: "You must judge for yourself. If I say it was a penalty and a red card then I am a bad loser. It was a very bad tackle."
Insult was added to injury for United as Moreno levelled Memphis Depay's opener before Luciano Narsingh netted a winner for PSV.
The manager said: "It is the same game as against Swansea [United's 2-1 Premier League defeat in Wales last month]. We dominate the game, create chances but we are not finishing."
Shaw quickly took to Twitter to thank former club Southampton after they had sent a tweet wishing him well in his recovery.
He replied: "Thank you, you don't know how much you as a club mean to me, thank you so much I really appreciate it."
The 20-year-old then tweeted: "Thank you everyone for your messages, words can't describe how gutted I am, my road to recovery starts now, I will come back stronger."
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