Australian Open 2015: Defending champion Stan Wawrinka moves into quarter-finals with victory over Guillermo Garcia-Lopez

Wawrinka overcame a mid-set slump to see off Garcia-Lopez 7-6 6-4 4-6 7-6

Stan Wawrinka came through his fourth round match against Guillermo Garcia-Lopez to reach the quarter-finals (Getty Images)

Defending champion Stan Wawrinka breathed a sigh of relief after claiming his place in the quarter-finals of the Australian Open on Monday.

Wawrinka looked to be cruising into the last eight in Melbourne when he led Spain's Guillermo Garcia-Lopez by two sets to love and 4-2 in the third.

However, the fourth seed then lost the next four games in succession and trailed 5-0 and 6-2 in a fourth-set tie-break before clinching a 7-6 (7/2) 6-4 4-6 7-6 (10/8) victory in three hours and two minutes.

Wawrinka said: "It was a real battle today. I was two sets up with a break and in the end I'm happy to get through. There was a good level of tennis in general and it's good to make one more win.

"At this level, things can change quickly. I did maybe two mistakes, then he start to play a little bit faster, a little bit more flat. I started to be defensive a little bit too much.

"Losing 5-0 was a bad start to the tie-break. At 6-2 I knew it was close to come back because I had the wind with me. I had to focus on every point. I knew if I was going to get it back to 6-5, he was going to get nervous. I did a good passing shot along the line and just focused point after point.

Stan Wawrinka signs autographs for fans after seeing off Guillermo Garcia-Lopez (Getty Images)

"I'm happy to get through. It is great for me to be in quarter-final and still there. I'm not focused on winning (another) major. I know it's difficult to do it. It's amazing I already did one. I'm taking it match after match."

The match was played on Margaret Court Arena after it was officially re-opened by the eponymous 24-time grand slam singles champion, although play was embarrassingly delayed for several minutes in the first set due to water dripping onto the court from the new retractable roof.

Guillermo Garcia-Lopez was unable to halt Wawrinka despite a third-set fightback (Getty Images)

Wawrinka will face fifth seed Kei Nishikori in the last eight after the US Open finalist beat Spain's David Ferrer 6-3 6-3 6-3. Nishikori won the pair's last meeting in the quarter-finals at Flushing Meadows last season.

PA