Belgium goalkeeper Thibaut Courtois has withdrawn from the squad for the first two World Cup qualifiers this month because of a back injury.

Real Madrid confirmed Sunday that Courtois was diagnosed with sacroiliitis – inflammation of the sacroiliac joints connecting the lower back and pelvis.

"The medical staff of Real Madrid and the Royal Belgian Football Association have discussed Thibaut Courtois’ back problems intensively in the past period,” the Belgian association said in a statement.

"Both medical staffs have concluded that the goalkeeper is not fit for the upcoming internationals.”

The injury could also jeopardize Courtois’ chances of playing at the Club World Cup in the United States, where Real Madrid begins its campaign June 18 in Miami against Al Hilal of Saudi Arabia.

Uncapped Nordin Jackers of Club Brugge will replace Courtois in the Belgian squad for the matches against North Macedonia in Skopje on Friday and at home against Wales next Monday.

Nottingham Forest goalkeeper Matz Sels is expected to start in goal for the two Group J fixtures.