Andre Agassi strolled through to the last four of the Australian Open today when Frenchman Sebastien Grosjean retired from their quarter-final with a groin strain.
Defending champion Agassi was leading 6-2 2-0 when ninth seed Grosjean informed the chair umpire that he could not continue.
Agassi, chasing his fifth Australian Open title, was in clinical form against Grosjean, racing to a 4-0 lead and taking the first set at a canter.
Grosjean, who had been struggling to keep pace with Agassi, called for the trainer at the end of the seventh game and took a pain-killer to ease his discomfort.
But he failed to recover and, apologising to Agassi, finished the match after just 44 minutes on court.
Agassi will play either world number one Andy Roddick or Russian Marat Safin in the semi-finals.
In the women's tournament, top seed Justine Henin-Hardenne wore down Lindsay Davenport of the United States 7-5 6-3 to book her place in the semi-finals.
Henin-Hardenne, the world number one and tournament favourite, used her superior court speed to blunt the power of Davenport, recovering from a slow start to wrap up victory in 87 minutes.
She will play Fabiola Zuluaga for a place in Saturday's final after the Colombian Zuluaga won a walkover from injured Frenchwoman Amelie Mauresmo.
PA