Everton midfielder Darron Gibson is to undergo surgery after suffering a right knee injury, the Premier League club announced Wednesday.
Gibson sustained anterior cruciate ligament damage during the Republic of Ireland's 3-1 World Cup qualifying win over Kazakhstan in Dublin on Tuesday and was carried on a stretcher.
Following a club medical assessment regarding the 25-year-old, an Everton statement said:
The 25-year-old was assessed by club medical staff on his return to Everton and, following confirmation an operation will be required, a lengthy lay-off is likely.
A statement on the club's website, evertonfc.com, read: "The length of time the 25-year-old will be out of action will be best determined once the surgery is completed.
"However, the scans did confirm to Everton's medical team that no additional damage was sustained to the structure of the right knee, ensuring all treatment and rehabilitation will be focused on repairing the damaged ACL."
The injury was another setback for Gibson who missed the start of the season with a different knee problem.
The injury is fresh blow for the player after missing the start of the season with a different knee problem.
His played his first Premier League game of the season against Manchester City on October 5, prior to his international recall.
Gibson made himself unavailable after Euro 2012 but the recent exit of manager Giovanni Trapattoni led to a return to Ireland duty for the final two World Cup qualifiers under interim boss Noel King.
He played 90 minutes against Germany last Friday but lasted just 37 against Kazakhstan, a match watched by Everton manager Roberto Martinez.