Manchester United head coach Erik ten Hag has said that he is unsure of the seriousness of the injury suffered by Luke Shaw in Wednesday's Premier League clash with Brentford.
The left-back was substituted in the 37th minute of the contest, and he appeared to hold his hamstring before heading down the tunnel for treatment.
Man United returned to the top four in the Premier League table courtesy of their 1-0 success over Brentford, with Marcus Rashford scoring the only goal of the match in the first period.
Shaw's injury will be a concern ahead of a busy run of matches, though, with the Red Devils having another seven games before the end of the month.
"In this moment, I can't give something about it because we have to wait for 24 hours," Ten Hag told MUTV on Wednesday night. "Then you can make the right diagnosis. So I don't want to comment in this moment."
Shaw's availability for Saturday's league clash with Everton is now in severe doubt.
Even a slight strain could keep the left-back on the sidelines for two to three weeks, which would also rule him out of both legs of the Europa League quarter-final with Sevilla, in addition to potentially the FA Cup semi-final with Brighton & Hove Albion on April 23.
Shaw has been a vital player for the 20-time English champions this season, featuring on 36 occasions in all competitions, scoring once and providing six assists in the process.
Ten Hag was also keen to pay tribute to the team effort that it took to beat Brentford on Wednesday.
"I was really happy with the performance of Jadon Sancho and Antony, and Marcel Sabitzer, because they were a threat the whole game," the Dutchman added after the match.
"The return of Anthony Martial can help us, so we have options. The whole season we play across Europe the most games, more than other teams, so we need the squad, so everyone has to be ready to come in.
"You see in the end, Victor [Lindelof] coming in for a short period but that makes a difference.
"I think [it was] a very good performance. First half we played brilliant football and it's not easy against a very good Brentford. They defend really compact, high, or really deep, so it's not easy to create chances.
"On the ball, it was very good with the big engine - Bruno Fernandes - he played a brilliant game."
Man United are now fourth in the table, level on points (53) and games (28) with third-placed Newcastle United, who thumped West Ham United 5-1 on Wednesday night.
