Defending champion Stan Wawrinka will resume his title defense in Day Eight of the 2015 Australian Open on Sunday night in Melbourne, Australia.

Wawrinka, who defeated Rafael Nadal in an epic final showdown last year, will face unseeded Guillermo Garcia-Lopez of Spain in the fourth round at Margaret Court Arena. The match is scheduled to start around 10 p.m. EST.

Wawrinka is looking to pick up from where he left off during his straight-set victory against Jarkko Nieminen of Finland in the third round of the tournament, but the Swiss tennis star is not expecting an easy match.

The 29-year-old, who also defeated Marsel Ilhan of Turkey and Marius Copil of Romania en route to the fourth round, sees a tough fight against Garcia-Lopez, who defeated Wawrinka in the French Open last year.

"He's been playing really good. I saw him a little bit this tournament," Wawrinka said of Garcia-Lopez. "I lost against him last year French Open first round. We had some tough battle in the past. It's never easy. Think it will, again, depend a lot of me, the way I'm going to play, the way I'm going to find my game to be aggressive."

Novak Djokovic, who is eyeing his fifth Australian Open title, will also see action in the eighth day of the tournament. The top-seeded Serb will collide with Gilles Muller of Luxembourg on Monday morning at Rod Laver Arena.

Djokovic is coming off a straight-set win against 31st seed Fernando Verdasco of Spain, but the nine-time Grand Slam champion does not expect an easy win against Muller.

Djokovic said that Muller is playing at his best in the tournament, citing how the 31-year-old scored a four-setter win against 13th seed Roberto Bautista Agut in the second round and a straight-set win against 19th seed John Isner in the third round.

Aside from Wawrinka and Djokovic, fifth seed Kei Nishikori of Japan will collide with ninth seed David Ferrer of Spain in the fourth round. Their match is scheduled to start Sunday night, around 11 p.m. EST, at Rod Laver Arena. The winner of the match will face either Wawrinka or Garcia-Lopez in the quarterfinals.

Before the Nishikori-Ferrer match, top seed Serena Williams will also see action on the women's side against 24th seed Garbine Muguruza of Spain. Dominika Cibulkova of Slovakia will face Victoria Azarenka of Belarus in the opening match at Rod Laver Arena, Sunday, 7 p.m. EST.

Complete 2015 Australian Open Day Eight schedule and match times are available on this link. Fans can catch the action on ESPN2 and through live stream via WatchESPN and Australian Open Live.

For the latest sports news, follow Latin Post Sports on Twitter.   

FOR MORE AUSTRALIAN OPEN 2015 UPDATES, CLICK ON THIS LINK TO VISIT LATIN POST.COM'S SPORTS PAGE.