Brisbane - Richie McCaw scratched his head - and bit his tongue - after the Crusaders captain conceded the last-minute penalty that enabled the table-topping Reds to snatch a 17-16 Super Rugby victory at Brisbane's Suncorp Stadium on Sunday.

According to the New Zealand Press Association (NZPA), Australian referee Stuart Dickinson, who only controlled the Round 15 clash after former New Zealand match official Steve Walsh was ruled out with a calf strain, perplexed the Crusaders when ruling one last ruck infringement as they clung to a 16-14 advantage as the clock wound down.

The Crusaders were on the wrong end of the penalty count and the All Blacks captain was diplomatic when quizzed on his concession of the match-turning infringement.

"I'm always going to think I was right but the ref saw it a different way. It's pretty disappointing. Ben (Franks) counter rucked, I presumed that was considered OK. I presumed he went past the ball so it was out so I went and picked it up. He (Dickinson) said it was still in the ruck."

McCaw disagreed with the ruling but saw no point complaining.

"You don't say what you're thinking. I guess when you think you're in the right and you're not, what can you say? He's made his decision and he wasn't going to change it."

Crusaders coach Todd Blackadder understandably backed McCaw's version of events.

"It was counter ruck, which is fine, (the ball was) picked up at the back of the ruck and it's turned out to be a penalty."

Reds counterpart Ewen McKenzie denied the Reds were fortuitous to win a 12th consecutive match on their home ground.

"You can argue the merits of penalties the whole way through," he said.

"I don't see it as luck. We had the ball and worked multiple phases in front of their goal posts. One of the laws of rugby is the defensive team gets penalised more than the attacking team.