MELBOURNE, January 18- World number one Rafael Nadal progressed to the second round of the Australian Open after his Brazilian opponent Marcos Daniel retired during the second set with a knee injury on Tuesday.
The Spanish top seed, bidding for his fourth straight major title to complete a non-calendar year Grand Slam, was leading 6-0, 5-0 at the time of the Brazilian’s retirement with left knee trouble.
Daniel took a medical timeout after losing the opening set in 19 minutes and looked a disconsolate figure as he hobbled around centre court unable to chase down Nadal’s volleys.
After his sixth service break, Daniel walked to the net and conceded defeat to Nadal on 47 minutes.
Nadal was sympathetic with Daniel’s plight after being forced out with a knee injury in the quarter-finals to Andy Murray in last year’s Australian Open.
"It’s a terrible feeling to pull out of a match with an injury and I wish him all the best and a fast recovery," Nadal said. "If you are feeling bad you should not go on and it’s best for the recovery."
Nadal is chasing his second Australian title and his 10th Grand Slam trophy in Melbourne.
At last year’s US Open, Nadal became the seventh man in history to win all four Grand Slam titles and became the youngest man in the Open Era to do so.