Walters ruled out for Ireland's Belgium clash

"Jon Walters is not going to be fit so we will have to make at least one change. We will have a look at it and decide on it tomorrow morning," said O'Neill at a press conference in Bordeaux on Friday.

Stoke City forward Walters had been a serious doubt with an achilles problem that had been dogging him in the build-up to the tournament and forced him off in the second half of Monday's 1-1 draw with Sweden at the Stade de France.

He did not train at the Irish squad's base in Versailles, near Paris, on Thursday.

James McClean replaced Walters during the Sweden game and is a contender to start in the crucial Group E encounter with the Belgians.

Ireland saw group rivals Italy clinch qualification for the last 16 by beating Sweden 1-0 in Toulouse on Friday.

That result turned up the pressure ahead of the match in Bordeaux, in which O'Neill wants his side to reproduce their promising performance against Sweden.

"I think from the way the team played they will draw great strength from that," he said, indicating that, Walters apart, the line-up may be unchanged at the impressive Matmut Atlantique stadium.

"There have been a few days now (since the first game) and the main bulk of players who played most of that match have had time to rest up, and actually I think that game will have brought them on somewhat."

Belgium have been heavily criticised for their display in losing 2-0 to the Italians in their opening match, but former Celtic manager O'Neill refused to be taken in by what he saw in Lyon from the likes of Premier League stars Eden Hazard and Romelu Lukaku.

"They are talented, very talented. They would maybe look at us and some of our players don't play at the level they play at week in and week out," he said.

"Individually they are as talented as any side in the competition and if they went on to win (the tournament) it would not be a major surprise to me."