The speed of Cam Clark proved to be the difference Sunday as Sydney-based Super Rugby side Waratahs beat Top League champions Suntory Sungoliath 21-19 at Prince Chichibu Memorial Rugby Ground.

Though to be fair, the Waratahs wing was also helped by the laborious kicking routine of Suntory flyhalf Hikaru Tamura, whose conversion attempt was charged down by the Australian sevens player.

Tamura had earlier been given the benefit of the doubt when he was allowed to retake a kick after the Waratahs reached the ball and picked it up before the kicker was able to put boot to ball.

But the second time around — following a try by Kensuke Hatakeyama — referee Akihisa Aso ruled in favor of the Waratahs, denying the hosts two points.

"I haven't seen that in years," said Waratahs captain Matt Lucas. "There was a lot of confusion around it. But as far as we were concerned, as soon as the kicker starts his movement we are allowed to charge. It's quite an odd thing and you don't see it too often."

The crowd of 9,848 does not generally get to see as many substitutions either.

Rolling replacements were the order of the day with the game being a preseason friendly for Suntory and a mid-season training game for the Waratahs during the Super Rugby break.

And while it gave both coaches the chance to see what younger members of their squad can do, it also had a knock-on effect in terms of preventing any real continuity.

The stop-start unstructured affair initially played into the hands of the hosts more than the visitors, and tries from Masakatsu Nishikawa and Takuya Kitade against one from Michael Wells saw Suntory lead 14-7 at the break.

Hatakeyama's try in the 52nd minute saw Suntory, which was missing all its Japan internationals in addition to its foreign contingent such as George Smith, Matt Giteau and Joe Wheeler, stretch its lead.

But it was the Wallabies-less Waratahs who finished stronger with David Horwitz making the most of a sloppy Suntory pass to go over and Bryce Hegarty — the game's outstanding player — converting his own five-pointer in the 62nd minute to seal the win.

"We had our chances but didn't take them," rued Suntory coach Keisuke Sawaki. "But it was good to play a physical, international-standard side that put Super Rugby pressure on us."