Rafael Nadal is still in contention for his second Australian Open title six years after his first…

The 28-year-old tennis star defeated Kevin Anderson on Sunday in straight sets on Sunday, 7-5, 6-1, 6-4 in the fourth-round, to advance to the quarterfinals.

Nadal, the 2009 Australian Open winner, turned around the first set — and ultimately the match — in the 11th and 12th games. Nadal fended off five break points to hold, and then broke the 6-foot-8 South African’s serve in the next game to go on a roll in his fourth-round encounter.

“Today was the best match so far this tournament, no doubt about that,” Nadal said. “I’m starting to feel more comfortable with my movements, with my forehand, so that’s the only way that I have any chance to have success on the tough matches ”

Nadal, who lost in the Australian Open finals in 2012 and last year, is coming off an extended injury layoff and says he’s building momentum as he goes — thankful he got through a tough five-setter in the second round against U.S. qualifier Tim Smyczek.

“The chance to be in the quarterfinals after a tough period of time for me is a fantastic result,” said Nadal. “I was playing better than the days before. I felt myself with better rhythm in the legs, better rhythm with my forehand. The way that I improved my level is not the most important thing; obviously the victory is.”

Nadal had to laugh in his last game as he tried to ignore a distraction when his water bottles — famously always precisely placed near the side of the court either for routine or superstition — tumbled over and a ball boy repositioned them.

“Seriously it’s not bothering me,” he said.

The third-seeded Nadal, who lost last year’s final to Stan Wawrinka, will play No. 7 Tomas Berdych in the quarterfinals.

Nadal has an 18-3 record over Berdych and hasn’t lost to the Czech player since 2006.