Renowned marathon man John Isner needed two tiebreakers before putting away Spaniard Marcel Granollers to reach the third round at the Australian Open on Thursday.

The beanpole American 10th seed, who is expected to lead the United States in their Davis Cup tie in Australia in March, won 6-3, 7-6 (8/6), 7-6 (7/2) in two hours 20 minutes on Hisense Arena.

Isner, who is looking to surpass his best Australian Open performance of reaching the fourth round, will play either Spain's Feliciano Lopez or Guido Pella in the third round.

Isner is well remembered for his 2010 Wimbledon defeat of Frenchman Nicolas Mahut, winning 70-68 in the fifth set in a first round match that lasted just over 11 hours -- with a final set of eight hours and 11 minutes.