OSLO, Norway -- Manchester United manager Ole Gunnar Solskjaer confirmed that Eric Bailly is set to miss up to the next five months after undergoing knee surgery.

The defender damaged ligaments in his left knee during the 2-1 win over Tottenham in Shanghai and is now facing a lengthy spell on the sidelines after having an operation on Tuesday morning.

Sources have told ESPN FC that United are still in talks with Leicester over centre-back Harry Maguire but they are facing a race against time to get the deal over the line before the deadline on Aug. 8.

Bailly suffered the injury -- which happened when he caught his studs in the turf at the Hongkou Stadium -- in just his third game back after damaging ligaments in his right knee at the end of last season.

"He's had an operation and he will miss the best part of four or five months I would think," Solskjaer said after the 1-0 win over Kristiansund in Oslo on Tuesday.

"Hopefully we'll get him back around Christmas. It was positive news from the surgeon. He had the operation and he was positive that it was all repaired, and he'll be fine. That's good news."

Bailly was left in Manchester as the squad travelled to Norway on Monday along with Romelu Lukaku and Matteo Darmian. Lukaku, wanted by both Inter Milan and Juventus, is yet to feature this summer because of an ankle problem but Solskjaer is hopeful the striker will be able to train ahead of their final friendly against AC Milan in Cardiff on Saturday.

Solskjaer's team kick off their Premier League campaign against Chelsea at Old Trafford on Aug. 11.

"It was best for him [Lukaku] to stay home," said Solskjaer. "He wouldn't have been able to play. Hopefully he might be able to train in the next couple of days. Let's see what happens.

"You never know what happens in football. He's not been able to train but he's not been that bad that we had to send him home, we still had hope he was going to be fit to play in Australia, Shanghai and Singapore. But for this short trip, there was no point bringing him."

Juan Mata's stoppage-time penalty handed Solskjaer's team a narrow victory over Kristiansund to make it five wins from five this summer.

David De Gea was named captain for the night and Solskjaer said he was hopeful of appointing a permanent skipper soon with De Gea, Mata, Ashley Young, Nemanja Matic and Paul Pogba all in the frame.

"We'll see," said Solskjaer when asked about who will be United's next captain after the departure of Antonio Valencia.

"We have different kinds of captain types. There are vocal leaders, there are players like David with his merits and what he's done. He'll play the majority of the games. We'll announce something soon."