The Highlanders took down the Chiefs 30-27 to kick off of the Super Rugby season – and with it the start of referee controversies.

With 15 minutes to go, and the Chiefs holding a seven-point lead, a red card was produced - one that sparked controversy.

Highlanders midfielder Sio Tomkinson was shown red after a collision with Chiefs lock Brodie Retallick, which was deemed to be a no-arms tackle by referee Glen Jackson.

There didn't look to be a lot in the tackle, but after a delay in play, Jackson produced the red.

"You've made no attempt to wrap him. You've used your shoulder and it's direct to the head so, for you, it's a red card," he explained to Tomkinson.

Onlookers weren't too happy again as some claimed the referee was protecting the All Blacks star ahead of the World Cup in September.

"It seemed a little bit cloudy, the conversation at the start," Highlanders coach Aaron Mauger said of the referees discussing the offence.

"We'll have to go back a look through the laws and make sure our interpretation of what's going on there is bang on and have a look at the video. We've got a pretty disappointed Sio Tomkinson in the changing shed because he felt like he'd let the team down. It was a big moment for a young guy like that so we'll make sure we put the support around him and make sure we're really clear and what you can and can't do in those moments."

Retallick had to come off the park as a result of the collision, but said he was fine after the game.

"Yeah, the neck's a bit stiff. Body is feeling good otherwise," Retallick said.

"It would've been good to have come away with the win especially after the lead we took in at halftime, but credit to the Highlanders to come back and execute when we didn't quite get it right."

That wasn't the only incident involving the TMO, with the Highlanders denied a try within the first three minutes of the game.

Hooker Liam Coltman looked to have crossed over, only for TMO Aaron Patterson to rule the effort out - judging it to have been held up after a last-gasp effort from Chiefs halfback Brad Weber.

Fans took to social media to express their frustrations with the call, and predict a long season of TMO debates ahead.

But regardless, the Highlanders managed to overcome the controversial calls to stun the Chiefs at home, and kick off their season with a bang.