Melbourne - Defending champion Stan Wawrinka won a thrilling fourth set tiebreaker to down Spain's Guillermo Garcia-Lopez and book a place in the Australian Open quarter-finals on Monday.
The Swiss fourth seed prevailed 7-6 (7/2), 6-4, 4-6, 7-6 (10/8) in just over three hours and will play either Japan's Kei Nishikori or Spain's David Ferrer in the last eight.
Garcia-Lopez, who knocked Wawrinka out in the first round at last year's French Open, had four set points at 6-2 in the tiebreaker to take the match into a fifth set before the defending champion clawed back.
Wawrinka held match point at 7-6 before the Spaniard got a fifth set point only to again be denied. The Swiss then clinched it on his second match point.
Wawrinka looked to be travelling to a straight sets victory after winning the first two sets and up a break in the third, before the Garcia-Lopez fightback on Margaret Court Arena.
"That was a really tough battle today. I was up two sets and a break after it was really tough to get the first set," Wawrinka said.
"I am happy to get through after three hours. It was a good level and it's good to make one more round.
"We have already played a big match at the French Open and it's always tough to play him, he plays with a good rhythm and he puts a lot of pressure on you from the baseline, but I served well," he added.
Both players got four service breaks each, while Wawrinka hit 70 winners and made 61 unforced errors. He served at 63 percent and won 76 percent of his first serves.