Roy Keane has added fresh fuel to the fire in the dispute between the Republic of Ireland and Everton over James McCarthy.

The Ireland assistant manager has suggested that Everton's players “need to toughen up” following McCarthy’s withdrawal from a World Cup qualifier against Austria.

McCarthy, currently suffering from a hamstring problem, has missed much of Everton’s season through injury, yet played in qualifiers against Georgia and Moldova last month.

The midfielder was selected again for this month’s match in Vienna, which angered the Everton manager Ronald Koeman, who accused Ireland of “massively overloading” his player.

Keane, speaking to journalists ahead of the Austria qualifier, has now suggested that Everton regularly cause problems for Ireland when attempting to call up players.

“We’ve had a problem with Roberto Martinez [Koeman’s predecessor at Everton] previously. I always felt the Everton players were going to turn up on crutches or crawling in the hotel door,” he said.

McCarthy has barely played for his club this season due to injury (Getty)

“They shouldn’t be so quick to stop Irish players coming to play for Ireland. [Darron Gibson] misses a hell of a lot of games for Everton… so maybe they need to look at their own training schedule.

“I’m not sure when they last won a trophy, so maybe as a club, their players need to toughen up a bit,” Keane added.

Everton's last trophy came in 1995, when Paul Rideout's strike proved enough to beat Manchester United 1-0 in that year's FA Cup final at Wembley.

Keane has cause to remember the occasion; he was playing in midfield for United that day.

The Ireland assistant continued: “Why do we need a good relationship with Everton? They're lucky to have the Irish lads they've got there. Traditionally, Everton have always had brilliant Irish players, doing well for the football club.

“They shouldn't be so quick stopping Irish players coming to play for Ireland. I've experienced that myself.”

McCarthy played one full game and 80 further minutes during the last round of international fixtures, despite not playing for his club since 23 August.