Coutts, who turned 38 on Tuesday, had been hoping for an early birthday present when he fronted the judiciary panel on Monday night to plead for a chance to play against Royals.

But the veteran front-rower was instead left ruing a costly yellow card in the preliminary final last weekend and he will be relegated to water boy at Viking Park on Saturday.

The yellow card was Coutts' third of the season and has a punishment of an automatic suspension.

Wests had hoped would be Coutts cleared to play because two of his yellow cards were for repeated team infringements.

But the laws changed two years ago and closed the loophole, meaning any yellow card counts against a personal tally.

Royals flanker Luke Kimber has suffered the same fate and will join Coutts as a heartbroken spectator for the grand final blockbuster.

"We all thought that because it was a team yellow, it wouldn't count," Coutts said.

"It wasn't until well after the [preliminary final] that we realised that wouldn't be the case. We took it to the judiciary but we always knew it was a tough ask.

"That's life. You've got to go by the rules. But I'll still be at training and doing everything I can to help the boys this weekend."

Wests copped another knock on Monday when Brumbies flanker Rob Valetini was ruled out because of concussion after failing a return to play test. Valetini, 18, has been ordered to 19 days of rest.

The only hope Wests had of Coutts playing was a mistaken identity loophole if they could prove the referee penalised the wrong player.

But when you're a 38-year-old tighthead prop who started his Canberra first grade career in 1998, you're pretty hard to miss.

The news was hard to swallow for Coutts on the eve of his birthday and more than a decade after his last grand final heartache while playing for the Sale Sharks in the English premiership.

Coutts played every game of the season, but was told he wouldn't be playing in the grand final because of a rule allowing just two import players on the field at the same time.

The former ACT under-19 and under-21 big man has been on a rugby journey around the world, but desperately wants a Wests premiership before he retires.

"I'll still be at training on Tuesday night ... I'll be running water on game day and doing everything I can for the team," Coutts said.

"I could have got an injury or been dropped. I played almost every game at Sale [in 2005-06] and I got dropped.

"So I've been in the situation before. At the time it sucks, but you still want the team to do well. It takes more than 15 guys to win a premiership, and I'm confident the guys can do it."

Wests are chasing their first premiership since 2005 while Royals are on the verge of a remarkable achievement of winning every game this year.

JOHN I DENT CUP GRAND FINAL

Saturday: Royals v Wests at Viking Park, 3.25pm.