MANCHESTER, England -- Ole Gunnar Solskjaer admitted his gamble in bringing on Marcus Rashford against Wolves "backfired" after the Manchester United forward was forced off with a back injury.

- Stream replay of Manchester United's win over Wolves on ESPN+ (U.S. only)

Rashford lasted just 15 minutes of the 1-0 win at Old Trafford on Wednesday after a clash with Wolves defender Matt Doherty and is now a doubt for the trip to Anfield to face Liverpool on Sunday.

After coming on in the 64th minute, the 22-year-old was replaced with Jesse Lingard in the 79th minute and headed straight down the tunnel.

"It backfired," said Solskjaer, whose team will play either Watford or Tranmere in the FA Cup fourth round after beating Wolves for the first time since 2012.

"You have got to take them [risks] once in a while.

"He'll be tested in the next few days -- we have to see for Sunday. He couldn't run. He struggled a little bit with his back and got another knock. It didn't help."

Doherty appeared to knee Rashford in the back and after being substituted, he left Old Trafford unaided but walking gingerly.

"I didn't want to play him," said Solskjaer. "We needed the win, he was involved in the goal, but it backfired. We will do everything we can to keep him fit."

Rashford, United's top scorer with season with 19 goals, will be a big miss for Solskjaer's team if he is not passed fit to play at Anfield. Liverpool are yet to lose in the Premier League this season and United remain the only team to take points off the runaway leaders after Rashford's goal earned a 1-1 draw at Old Trafford in October.

After the game Rashford tweeted: "Never want to feel like I've let my teammates, the club and most importantly the fans down, so did my very best to carry on tonight and was gutted to come off. Top work from the lads to get into the next round."