Sepp Straka was the surprise leader of the golf competition after round one at Tokyo 2020 thanks to a dazzling and record-equalling eight-under 63 at Kasumigaseki Country Club.

The 161st-ranked Austrian sat one stroke clear of Jazz Janewattananond, with Thomas Pieters and Carlos Ortiz only two strokes back.

Play was delayed for around two hours on Thursday due to dangerous weather conditions and a host of star names were off the pace after the first 18 holes.

STRAKA SURPRISES TO EARN SHARE OF HISTORY

The unheralded Straka, whose twin brother is on his bag this weekend, tied the record for the lowest single-round score at an Olympics with his 63.

"It was just a steady round. I really hit the ball well and I didn't put myself into trouble. I took advantage with the putter," Straka said.

"I got hot with my irons, especially my short irons, my wedges. I was really knocking down the flagstick and really tried to stay aggressive."

He made four gains on the way out and as many on the way home in a fine bogey-free round, and this round came despite him missing six of his past seven cuts.

HIDEKI, MCILROY AND CO HAVE WORK TO DO

Masters champion Hideki Matsuyama is carrying the home hopes in Tokyo this week and was six shots back.

He was four under through eight but gave one back before the turn and dropped another shot at 11.

Rory McIlroy and Open victor Collin Morikawa are also at two under, with Patrick Reed five back and Justin Thomas at evens after making 18 pars.