The Stats Insider Futures Model is signalling a two-horse premiership race after 14 rounds of the 2021 NRL season. The Penrith Panthers and Melbourne Storm are in a league of their own, slotted in as 27.6% and 27.5% favourites to lift the Provan-Summons Trophy come season's end. 

Both are elite teams for different reasons. They've found what works and stuck with it to win 12 of their first 14 games and be equal on competition points heading into Round 15.

So, what has gone right for these two teams so far in 2021, and what would need to go wrong for them not to meet in the 2021 NRL Grand Final?

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What has gone right?

The Panthers are quite obviously one of the best-attacking teams in the NRL, but it's their defence that really sets them apart from the rest. 

Conceding just 7.3 points per game before State of Origin put a broom through their first-choice 17, the Panthers went unbeaten through the first 12 rounds. It took 169 minutes for Penrith to concede their first try of the season, and just one team (Sea Eagles, Round 8) managed to score more than 12 points.

A lot of their dominance in defence comes through continuity and cohesion. Penrith used the second-fewest players throughout the 2020 NRL season. Many of those same players returned for 2021, and so far, their 26 players used is again the second-fewest in the competition. Along with being blessed by the injury gods for a season and a half - *touch wood* - the Panthers have used their yardage game to build pressure and pin the opposition in their own end. 

Penrith leads the NRL in yardage with 1,884 running metres per game. They charge up the field to earn the second-most tackles inside the opposition 20-metre line at 32.8 per game, and add to them with an NRL-high 2.2 forced dropouts per match. They build pressure and are patient in sustaining it. If points don't come - they often do at 29.9 points per game - the opposition is forced to work the ball out from their own ten-metre line more often than not.

Defence, yardage and pressure have been the recipe for Penrith's success so far in 2021.

Meanwhile, the Storm's all-out attack has seen them run teams off the park to the tune of 33.7 points per game. They've cracked 40 points eight times already this season and averaged an outrageous 38.5 points per game throughout their 11-game winning streak.

Melbourne breaks down teams all the way up the field, moving the defensive line around and creating instability in the defensive line.

Their 67.7 one pass hit-ups per game is the fewest in the NRL. Using long passes out of dummy half to ball-playing middles, Melbourne is able to set their key ballplayers up down the edges to run against a retreating or sliding defensive line. It has unlocked Jahrome Hughes' outstanding running game and allowed stand-in fullback, Nicho Hynes, to pick his moments with the ball as a running or passing option. 

Moving the ball not only contributes to their 33.7 points per game, but it puts Melbourne up at 3rd in yardage with 1,725 running metres per game and, like Penrith, sets up a strong defence conceding just 12.7 points per game.

Flamboyant teams of the past like the 2019 Roosters weren't afraid to push the pass in attack and back their defence if it didn't come off. The Storm, on the other hand, are throwing it around while making just 9.1 errors per game - the second-fewest in the NRL.

Melbourne's defence is already at a premiership-winning level, and their NRL-best attack might only just be getting started. 

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What might go wrong?

These two teams are expected to meet in the 2021 NRL Grand Final for a rematch of the 2020 edition. While the fixture already appears locked in for October 3, we know better than to assume anything is guaranteed in the NRL. 

For the Panthers, injuries are a big consideration. 

"Luck" isn't a word fans like to hear and it often triggers an instant defence of their side, but the Panthers have undoubtedly been blessed with some injury luck over the last 18 months, and as Round 13 and 14 has proven, they're not all that well-equipped to deal with too many at this point. The Storm and Roosters have been forced to deal with Origin and injuries throughout their dominant periods and can plug and play different players into the side when necessary. The Panthers, on the other hand, don't have that experience through the side just yet.

Back-to-back losses have been over-analysed and criticised. 

However, this fortnight without six or seven stars has given Ivan Cleary's depth players valuable time in different roles and could end up preparing them for big games later in the season if injuries strike. Craig Bellamy has used 29 or more players in each of his last four seasons - sometimes by design. He will trot out the likes of Max King, Darryn Schonig, Aaron Pene, Chris Lewis and Trent Loiero throughout the year to gain some experience and be prepared for the call if it comes later in the season. 

With the winning streak over, a Top 4 finish locked in (97.6%) and a Top 2 finish likely given their points differential, Cleary may start to rotate through his squad both in preparation for, and attempt to avoid, an injury crisis further down the track.

As for the Storm, we already know that they deal with injuries better than any team in the competition. While a continuation of injuries is an obvious 'what could go wrong' scenario for Bellamy, an off night or lack of close games throughout the year is about the only other hurdle on the cards for this group.

Melbourne is winning by an average of 25 points per game this season. Before their 20-12 win over the Titans in Round 13, they'd set a new NRL record for most consecutive wins by 13+ with eight on the bounce. 

They've barely been challenged since dropping two games in Round 2 and 3. A middling draw won't provide them with too many close contests before finals football kicks off either. Playing the Panthers in Round 20, Sea Eagles in Round 21 and Eels in Round 24 gives the Storm just three more games against genuine contenders. 

Dominating a regular season is nothing new for the Storm. However, this is one of the softest competitions in recent memory. Every other week is a training run and the top-tier teams are barely breaking a sweat. It's unlikely to be what derails Melbourne's season, but there doesn't appear to be anything else that could get in the way of this Storm juggernaut in what might be Bellamy's last year with the club. 

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Crystal Ball

The Panthers have a slightly more difficult draw through to Round 25. While Melbourne plays just three more of the top sides, Penrith has two against the Eels, a Round 23 matchup with the Rabbitohs, their clash with the Storm, and two possibly difficult matches with the Roosters to come. 

The race to the Minor Premiership is down to two with the South Sydney Rabbitohs the next best at just 10%. There is little else for the Storm and Panthers to play for through to Round 25. 

Melbourne sit at the top of the NRL ladder and have a slightly superior for and against after Round 14. Still, Penrith is the model's favourite to finish 1st. It's more than likely that both will hold home ground advantage through to the Grand Final, though.

These two teams are incredibly even. They're head and shoulders above the rest and will be remembered as two of the best regular season teams in NRL history if they keep this up.

Dominant in both attack and defence, and with lengthy winning streaks throughout, it's Penrith and Melbourne's competition and the other 14 teams are just playing in it.

I'm leaning towards Melbourne going back-to-back right now. But it's only a very slight lean. They've been there and done it all before, and with the injury and suspension issues they've faced so far, Bellamy can still get more out of this group. I don't think we can underestimate Bellamy's probable departure being a factor later in the year.

Penrith will be better for the experience of last year. As much as they've been stung by Origin recently, those selected will be better for that experience too. However, Bellamy and the Storm have been doing this for almost 20 years.

With the two teams so close, and a third unlikely to force their way into the conversation any time soon, it comes down to which side you trust more.

For me, that's Melbourne.

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