Neil Robertson of Australia plays a shot in the second semi-final match against Ronnie O'Sullivan of England at the Hong Kong Masters snooker tournament in Hong Kong on Oct 8, 2022. (PETER PARKS / AFP)

LONDON - Defending champion Neil Robertson and three-time winner Mark Selby were both ousted from snooker's 2023 Masters in the opening round on Sunday.

Robertson, 40, took the first frame with a break of 73 against Shaun Murphy, but then lost five frames in a row in Sunday's first match at London's Alexandra Palace.

The Australian managed to take three frames back, but Murphy sealed the victory by winning the 10th frame.

World No 2 Mark Selby was stunned by tournament debutant Hossein Vafaei, as the Iranian made two centuries to win 6-2

"I'm delighted," Murphy was quoted by the World Snooker Tour website. "It looked like we were going to a decider. The break I made in the last frame, I'm very proud of that to be able to stand up under pressure. "

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Later, world No. 2 Selby was stunned by tournament debutant Hossein Vafaei, as the Iranian made two centuries to win 6-2.

Vafaei made his Masters debut on Sunday as he replaced China's world No. 9 Zhao Xintong, who was suspended for being under investigation into allegations of match fixing.

After splitting the first four frames with Selby, the 28-year-old took four frames in a row to advance.

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Vafaei will face either John Higgins or Jack Lisowski in the quarterfinals, while Murphy waits for the winner between Kyren Wilson and Stuart Bingham.