Richard Gasquet delivered the shot of the match—a brilliant backhand down the line that dotted the baseline and saved match point—but Bernard Tomic kept his concentration to win the most dramatic match of the day in Shanghai.

Tomic unloaded a couple of flat forehands to break Gasquet in the epic final game of an entertaining 6-3, 6-7 (1), 6-4 victory at the Shanghai Rolex Masters.

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It was Tomic's 39th win of the season and second straight win over a Top 15-ranked player following his straight-sets sweep of No. 8 David Ferrer.

It was also Tomic's first win over Gasquet since a 7-6 (7), 5-7, 7-5, 7-6 (5) decision at the 2013 Wimbledon and sent the 22-year-old Aussie into his ninth quarterfinal of the year. Tomic will take on world No. 1 Novak Djokovic for a place in the Shanghai Rolex Masters final four.

Tomic, who dropped to No. 71 in the rankings in January, is now ranked a career-best No. 20 and could crack 40 wins in a season for the first time in his career.

The man players once called "Tomic the Tank Engine" for his penchant for giving up in matches, says growing mentally tougher has been a key to his most successful season on Tour.

"You have to be mentally very strong," Tomic told the media in Shanghai. "I think you want to always play limited tournaments. I think this year one thing I didn't do well, I played a lot of tournaments. I did well in a lot of them, so it kept me going, kept me pushing to play more, which was in one way good from a results point of view, but for my body it was probably bad playing this many tournaments."

Contesting his 24th tournament of the year this week in Shanghai, Tomic says he will reduce his workload in 2016.

"I can look at next year and obviously cut down a lot more tournaments," Tomic said. "Yeah, but like I said, the tour is very tough. It's only meant for the really strong in the head."