China's Wang Qiang pulls off stunning opening-round upset at Australian Open

China's Wang Qiang hits a shot during her first round match against Sloane Stephens of the US at the Australian Open tennis tournament at Melbourne Park, Australia, January 18, 2016. [Photo/Agencies]

Wu said he was confident he had the game to compete among tennis' elite despite the straight sets drubbing.

"It's my third try to get past the first round here - I'm feeling not that happy," Wu told reporters on Monday after his disappointing loss.

"But I think I'm a good player and hope I can go further (than the first round)."

Wu, China's third-highest ranked player on the ATP Tour at 240, had never made it past the first round of any Grand Slam, and didn't fair any better in his third appearance at the Australian Open against the American.

Krajicek equaled his best performance at the Australian Open progressing to the second round for the second consecutive year.

He will now play Japan's Kei Nishikori, Asia's highest ranked player, in the second round.

Despite a tough first round draw, Nishikori cruised past Philipp Kohlschreiber 6-4, 6-3, 6-3.

The match shaped as a tricky opening game for the number seven seed, with his world-number-32 opponent just missing out on a seed at the first Grand Slam of the year.

But the 26-year-old kept his quest for a fifth straight apperence in the tournament's second week alive, winning inside of two hours.