If Parramatta Eels roll Penrith Panthers in Sunday’s grand final, they will become the biggest head-to-head betting outsiders to lift the trophy in the NRL era. 

As of Thursday morning, the Eels had drifted to $3.20 to claim their first premiership since 1986, with the Panthers $1.35 to become only the second team in the NRL era to successfully defend the title.

And as recent history shows, it’s a tough road for anyone but the narrowest underdogs to spring a grand final day upset.

A history of grand final boilovers

Arguably the most celebrated of all shock grand final results was Balmain’s 11-2 defeat of two-time defending champs South Sydney in 1969. Regarded as 3/1 underdogs in the days before legal sports betting, the Tigers employed contentious go-slow tactics to thwart the star-studded Rabbitohs.

Genuine grand final upsets were rare throughout the 1970s and ‘80s, though Canberra was considered a distinct outsider against Balmain in the epic 1989 decider. The Raiders rallied from 10 points down at halftime to win in extra-time – becoming the first team to take out the title from fourth spot in the five-team finals era.

The Bulldogs pulled off the unlikeliest grand final win of the past 50 years in 1995. Surging to the decider from sixth after being torn asunder by the Super League war, the blue-and-whites stunned a Manly side that had lost just twice all year 17-4 in the big one.

Melbourne pulled off a heart-stopping 20-18 win over St George Illawarra in the 1999 grand final as underdogs, having lost to the Dragons 34-10 in week one of the finals. Runaway 2001 minor premier Parramatta was just $1.40 to cap a dominant year with grand final glory, before suffering a first-half ambush at the hands of Newcastle and ultimately going down 30-24.

Penrith (2003) and Brisbane (2006) snared moderate grand final upsets against Sydney Roosters and the Storm, respectively, in low-scoring deciders.

Favourites thrive in recent times

Since 2009, just three NRL grand final underdogs have got up – and they were among the shortest-priced outsiders of that period.

North Queensland Cowboys were $1.97 ahead of the 2015 decider against Brisbane Broncos, the hardest to split of any grand final combatants in recent history. The Cowboys snared their maiden title 17-16 via a Johnathan Thurston field goal in the first grand final in 26 years to require extra-time.

Twelve months later, Cronulla Sharks won their first premiership in emotional scenes with a gripping 14-12 win over Melbourne Storm. The Sharks were $2.05 outsiders.

It’s easy to forget Sydney Roosters were the underdogs heading into 2018 grand final before comfortably accounting for an uncharacteristically flat Storm outfit 21-6. The Roosters headed into the decider $2.12 in the head-to-head stakes.

Tough trend for big outsiders

Three teams have gone into an NRL grand final in the past decade as an underdog of $3 or more – with two justifying their price by enduring heavy defeats.

After embarking on an unlikely charge to the 2014 decider from seventh, the Bulldogs were $3.27 outsiders against the Rabbitohs. They were duly pumped 30-6 after drawing level at 6-all early in the second half.

Another bolter, the 2017 Cowboys, weaved their way through the playoffs from eighth spot. They were $3.89 to complete the fairytale against the Storm but were never in the grand final, crashing to a 34-6 loss.

The best-performed NRL grand final longshot of recent times were the Raiders in 2019, listed at $3.45 to prevent the Roosters from going back-to-back. The scores were locked 8-all late in an absorbing showdown before a controversial ‘six-again’ call reversal changed the tide and the Roosters produced a long-range match-winner for a 14-8 result.

South Sydney went desperately close as $2.30 underdogs last year, edged out 14-12 by Penrith in the Suncorp Stadium-hosted grand final.

While many are prepared to give Parramatta a decent chance at winning the 2022 grand final, there’s no question – from a betting perspective, at least – it would rank among the great upsets on the NRL’s biggest stage.