Wayne Hennessey will have an injection in an attempt to be fit for Wales’ Euro 2016 match against England on Thursday.
The Crystal Palace goalkeeper was replaced by Liverpool’s Danny Ward for Saturday’s Group B win over Slovakia after suffering a back spasm.
However, Hennessey expects to return to training quickly, and to be ready for the game in Lens.
“It is one of those things where you go from broke to mended in about 24 hours,” the goalkeeper said.
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Hennessey suffered a similar spasm before Palace faced Liverpool in the Premier League in March.
“I had one and missed the Liverpool game at home for Crystal Palace,” he said.
“So I’ll have an injection now and I will probably be back in 24 hours, which sounds crazy.
“It was an unsettling time for myself, but our motto is ‘Together Stronger’ and it is all about the boys.”
Ward made his first international start in Bordeaux on Saturday, helping Wales to a 2-1 victory.
Hennessey said: “I thought Danny did really well. It was a big situation for him to come in but I thought he was tremendous.”
Meanwhile, Aaron Ramsey says that Wales will focus on themselves and not be too preoccupied about England.
Chris Coleman’s side lead Group B after England drew 1-1 with Russia in Marseille.
“They had a faultless [qualifying] campaign,” Arsenal midfielder Ramsey said.
“They have a lot of good players, who are quite dangerous individually.
“But we will focus on ourselves and what we need to do to try and get something out of the game.”
Wales became the first British team to win their opening game at a European Championship with victory over Slovakia.
“We wanted to start off well in this competition and we’ve managed to do that,” Ramsey added.
“We work hard for each other, we have quality going forward and we are ready to take on anybody.”