Have the Cowboys paid too much for Jeremiah Nanai?

Boom second-rower Jeremiah Nanai has confirmed his future, signing a four-year extension with the North Queensland Cowboys that will keep him at the club for the next five seasons - at least until the end of 2027.

While reported figures must always be taken with a grain of salt, on this particular occasion, it's believed the deal is worth $3.6 million - or about $900,000 per season.

That, for a player who is approaching the start of his second full season in first-grade, is an awful lot of money.

And yet, the fact that this is a question rather than an outright statement goes to show just how impressive Nanai's first season at the Cowboys was.

His attack was first-class, and he quickly became one of the best forwards in the competition - a salary he now has to match.

It was an impressive display of confidence in his own ability from the young gun too. When he was able to negotiate for 2023 at the end of 2021, he fielded interest from a number of clubs in a possible long-term deal, but ultimately decided on signing a one-year extension in Townsville, clearly backing his market value was going to rise again.

And didn't it ever. The display of confidence was rewarded in a big way, with Nanai ultimately lining up for Queensland at State of Origin level, before touring to England for the Rugby League World Cup with the Kangaroos, who ultimately took out the tournament.

The Cairns junior had a whirlwind 2022, scoring 17 tries in the NRL - the most of any forward, and the most of any forward in Cowboys' history, so good was his season. In fact, by the time it was all said and done, only Alex Johnston, Corey Oates, Murray Taulagi and Ronaldo Mulitalo had scored more tries than Nanai in his 23 games.

That means Nanai out-scored the likes of Josh Addo-Carr, Taylan May, Xavier Coates, Daniel Tupou and the wingers who took the NRL by storm in Selwyn Cobbo and Joseph Sua'ali'i, who, like Nanai, were in their first full seasons of first-grade, having both debuted at the back-end of 2021.

In addition to his 17 tries, Nanai made 8 line breaks, 18 offloads and ran for a tick under 100 metres per game. It was a phenomenal season.

But the easy and smooth transition into a first-grade weapon didn't carry over to his defence, and while there are worse defenders than Nanai, for a player who is now going to be among the highest-paid at the club - realistically only behind Jason Taumalolo - it's a side of his game that will need to improve rapidly.

Nanai was, particularly in the first half of the season, caught out of position or clutching at thin air on more than one occasions, failing the eye test.

But it's the stats that back it up which will leave a little bit of worry.

Nanai missed 79 tackles in 2022 at an average of over three per game, and he ultimately had a tackle efficiency rating of less than 90 per cent. He also had another 38 ineffective tackles that aren't counted in that percentage rating.

The percentage sitting under 90 leaves him as the sixth-worst tackler based on that stat alone of all the players who regularly played second-row in 2022 and made more than 200 tackle attempts.

The players who sit behind him? Kelma Tuilagi, Jaydn Su'A, Viliame Kikau, Jaydn Su'A and Kurt Capewell.

While Kikau and Martin's name sitting there is a surprise, the Panthers are able to cover for that through their excellent set up in defence and control through the middle third.

That in itself is enough of a worry for the Bulldogs, who have signed Kikau.

The Cowboys covered for it well enough last year to find themselves in the preliminary finals, but to go to the next level without the set up of Penrith - players like Nathan Cleary, Jarome Luai and Apisai Koroisau in attack, you have to wonder if they will be able to do that with a crucial position not being defended well enough.

When you compare Nanai's new salary to that of the rest of the league, it's easy to see just how well-paid Nanai is about to be.

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While Kalyn Ponga comes in as the highest-paid player in the game on a reported salary of $1.4 million per season (ratchet clauses pending on salary cap increases), the game's highest-paid forward is believed to be David Fifita on $1 million.

Again, all of these figures are reported, but Nanai's new contract will leave him only behind Fifita, Jason Taumalolo and Tevita Pangai Junior when it comes to forwards who earn more than him.

Fifita's well-noted issues with attitude and defence don't even place him behind Nanai in the pecking order when it comes to tackling efficiency, and while a single stat isn't the end of the world, the eye test doesn't do Nanai any favours.

Not only was he caught out of position at times in 2022, his technique still leaves a little to be desired in the defensive line.

Multiple clubs went after him, and you can only assume they were all in the same ball park money-wise for the Origin debutant, but even in that environment, with what should be a structure that works, he missed six tackles across the first two games off the bench, playing a combined total of 65 minutes.

He then missed eight tackles in Game 3 after starting, giving him 14 misses from a combined 77 attempts - leaving him tackling at just 81.8% during the representative fixtures.

That's not to say he can't improve, because he has the right attitude to continue improving that side of his game, but the Cowboys shelling out such a significant portion of the salary cap over such a long period of time is a risk.

Nanai will also have the dreaded second-year syndrome to deal with this year - something that has claimed plenty of players. You only have to look at the rise and fall of Jamayne Isaako to know just how much that can de-rail a player.

This is nothing against Nanai - his attack alone is probably worth what the Cowboys have paid him, but if it falls away, then his defence simply isn't up to scratch to justify the money, or his standing.

And that, for a team who had a breakout 2022 but need to repeat the dosage in 2023 to rubber-stamp their authority as one of the NRL's top outfits under Todd Payten, is a cause for concern.