Super Rugby Pacific: Highlanders halfback Aaron Smith battles above weight class against Melbourne Rebels lock Josh Canham

Over the years, rugby halfbacks have won a reputation for their sharp tongues and quick tempers - and All Blacks veteran Aaron Smith is obviously no different.

As his Highlanders battled to a much-needed 20-17 Super Rugby Pacific victory over Melbourne Rebels at Dunedin, the pint-sized No.9 left his modest weight class to take on giant lock Josh Canham in a genuine David-and-Goliath clash.

In UFC terms, at 83kg, Smith would sneak into the middleweight division, while Canham (115kg) is a true heavyweight. The height discrepancy is even more marked, with Canham towering a full foot (31cm) above his rival.

Aaron Smith in action for the Highlanders
Aaron Smith in action for the Highlanders. Photo credit: Photosport

That mattered little, when the Rebels forward lashed out at Smith with his foot, as the pair picked themselves up from a ruck, and the halfback took exception.

Teammates rushed in to break up the mismatch, although neither combatant showed any sign of backing down, much to the amusement of Sky Sport commentators.

"He's well out of his weight division, Marshy," chuckled former Highlanders lock Joe Wheeler.

"He's hanging in there well though," observed former All Blacks halfback Justin Marshall.

"What's that old saying - it's not the size of the dog, it's the fight," replied Wheeler. "There's plenty of it in Aaron Smith, gee wiz!"

When the dust settled, referee Paul Williams awarded a points decision to the smaller man, penalising Canham for the initial offence.

Now the second-most capped Super Rugby performer, behind former Crusaders prop Wyatt Crockett, Smith also had the last laugh on the scoreboard, as his team snapped a five-game losing streak to keep their playoff hopes alive and deliver a blow to those of the Rebels.