The Wallabies have suffered a heart-breaking series loss to the British and Irish Lions after letting slip an 18-point lead to crash to a 29-26 defeat in the final minute of their second Test at the MCG.

The Australians looked set to level the series after a rousing opening 30 minutes but the Lions roared back with fullback Hugo Keenan scoring with 45 seconds left on the clock for his team to take the lead for the first time in the match.

The game ended in controversial circumstances with the Wallabies flanker Carlo Tizzano appearing to have been illegally cleaned out in the build-up to the match-winning try.

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While the TMO and referee Andrea Piardi reviewed the clean-out by Jac Morgan, he didn’t deem it a penalty and the try stood.

Former Wallabies centre Morgan Turinui blasted “weak” referees over the controversial decision.

“The referees were too weak to give it (the penalty),” he said in commentary.

“You cannot hit a guy in the back of the neck to save the ball who is legally jackling.

“The referees have got it wrong. It has cost the Wallabies survival in the series.

“The British and Irish Lions lead this series 2-0. It was brave to come back from them, but it is a terrible decision that decides this match.”

Ex-England and Lions skipper Martin Johnson took a contrasting view, but former Wallabies captain Michael Hooper agreed with Turinui.

“I can see what the referee’s saying but there’s a penalty there, whether it’s on head, on neck or whether he’s going straight off his feet to ground,” Hooper said on Nine.

“I would say if that was minute one it’s a penalty and it was deserved to be awarded and the try overturned.

“If you’re refereeing or judging by the letter of the law, minute one to minute 79 it doesn’t matter.”

Johnson disagreed.

“I didn’t think there was enough there for a penalty that would change the game,” he said on Nine.

“You have to be very, very sure to change the game on a ref’s decision.

“I thought it wasn’t a penalty.”

Gutted Wallabies captain Harry Wilson was asked in a post-match interview about the decision but said he “wasn’t in the right emotion to talk about it”.

Coming after the Wallabies loss in Brisbane, the Lions will lift the Tom Richards Cup with a third Test still to play in Sydney.

The result means the Wallabies are the first team since the 1966 Lions tour to lose the series in two games, with that Australian outfit losing both matches in a two-Test tour.

Wilson said he was proud of the way his team played.

“I’m so proud of this team - we were written off, we came out here and put our bodies on the line and was there until the very end,” the No.8 told Stan Sport.

“To lose like that, it hurts.

“I hope everyone at home and everyone here saw what kind of team we had - we are going to keep fighting and keep improving. We just want to do Australia proud.

“I’m gutted there’s not going to be a decider but if you think there’s not going to be a lot on the line next week you’re kidding yourself.”

In the Lions’ last two visits down under, in 2001 and 2013, Melbourne had been a happy hunting ground with the Wallabies drawing level after first Test defeats.

It appeared this series would also follow that script as the hosts came out firing in front of a crowd of 90,307, which was the largest ever to watch a Lions match in Australia.

With Will Skelton and Rob Valetini, who sat out the first Test through injury, adding size to the pack, the Wallabies answered their critics and aimed up early in a physical display that had the tourists on the back foot.

Two early penalty kicks by Tom Lynagh gave the Wallabies an early six-point lead and a boost of confidence but the Lions were first across the tryline in the 15th minute through hooker Dan Sheehan.

Prop James Slipper, only the second Wallaby to have played in two series then scored for an 11-5 lead and everything seemed to be going the home side’s way.

Lions winger Tommy Freeman was yellow-carded after his team’s multiple infringements and the Wallabies then raced out a 23-5 lead with halfback Jake Gordon and fullback Tom Wright both scoring.

But the tide started to turn and the Lions closed the gap to 23-17 by halftime, with flanker Tom Curry and centre Huw Jones touching down.

The second half was an arm wrestle and a 59th minute try by Tadgh Beirne set up a thrilling finale.

The Wallabies showed desperation in defence and it looked like they would hold on for a famous victory but the Lions had the final say.