Updated

Andy Murray has retired from his second-round match with Marcel Granollers in the second round of the Italian Open.

Murray walked off the court after winning the second set.

It wasn't immediately clear what was bothering the British player, although he took a long injury break early in the second set, getting his left thigh and lower back massaged. Granollers won the first set 6-3 and Murray won the second 7-6 (5).

Murray is celebrating his 26th birthday.