Belgium full-back Timothy Castagne has been ruled out for the remainder of Euro 2020 after sustaining a double fracture of his right eye socket.

Roberto Martinez's Belgium opened their Euro 2020 campaign with a comfortable 3-0 win over Russia on Saturday but it came at a cost.

Castagne and Russia's Daler Kuzyaev collided in mid-air after 25 minutes and both went down holding their heads.

Belgium's Castagne was substituted immediately and Kuzyaev two minutes later in the Group B clash in St Petersburg.

"Really bad news, really sad news to see Timothy Castagne is going to be out of the tournament," Belgium head coach Martinez said. 

"He's had images taken, he's got a double fracture and now we'll take the necessary treatment."

While Leicester City's Castagne will sit out the rest of the European Championship, the news was better for Jan Vertonghen. 

Veteran defender Vertonghen was withdrawn in the 77th minute due to ankle injury, but Martinez said there were no major concerns regarding his fitness going forward. 

"Vertonghen has got just a typical football injury, an ankle knock that we're probably going to wait 48 hours to see the real extent, but I don't expect it to be too serious," Martinez said. 

Overall, Martinez was satisfied to see his side play the way they did in the opener. 

"The performance is very pleasing," he said. "It's never easy to start a tournament of this magnitude and I think it looked a team very concentrated for 90 minutes, kept a clean sheet in a very good way, and then obviously the win will allow us to grow and to get into the tournament."

Belgium are unbeaten in 10 games in all competitions (W8 D2) and have suffered just one defeat in their last 24 internationals (W20 D3), via a 2-1 loss to England in the Nations League in October 2020.

Russia boss Stanislav Cherchesov will have far more to worry about after an uninspiring performance but expressed optimism his side will bounce back against Finland on Wednesday.

Cherchesov's Russia have lost four of their last six competitive games (W2) after losing just one of their 13 before that (W10 D2).

"We are still in the tournament," Cherchesov told a news conference. "We chose our system, which worked partially but then started to break down. The Belgians scored and then it was difficult to get the ball off them."

"We will get out of the situation. We put ourselves there, so now we must find a way out."