The NRL is in the midst of its closest start to a season since 1975, with league bosses hopeful the tight margins indicate tweaks to the rules are working.

Teams have won by an average of only 8.58 points across three rounds to start 2023, down from 8.75 for the same period last season.

Of the 24 games played thus far, 12 have been decided by a converted try or less and 18 by 12 points or fewer. The largest winning margin has been only 25 points - one of only two games decided by 20 or more points.

The statistics are in direct contrast to the two seasons immediately after the NRL introduced its six-again rule change.

Some teams struggled to adapt to the new pace of the game after the six-again rule came in in 2020; the average winning margin across the first three rounds of 2020 was 13.42 and increased to 15.71 the following season.

At the time, pundits claimed the rule change had impacted the spectacle of the game as the gap between the top and the bottom of the premiership had become too wide.

But the closer margins appear to vindicate the six-again rule and other relatively recent tweaks to the rules designed to keep the game flowing; since 2020, the NRL has also clamped down on stoppages in play for minor injuries, dialled back the number of instances a scrum is packed and have changed the way completed tackles are adjudicated.

NRL's head of football Graham Annesley said it was too early to determine whether rule changes were responsible for the closer games but believed the early signs were encouraging.

"I hope it's leading us towards that suggestion," he said.

"Time will tell, there are other factors.

"We have teams with injuries. We have heat playing a factor.

"We have the fact we started the competition with two weekends of organised pre-season, where normally in the first two rounds, teams are still trying to find their rhythm and their timing can be a bit off."

Annesley said NRL head office was not surprised some teams were only now beginning to adjust to the six-again rule.

Through three rounds this season, only three teams remain unbeaten: Manly and Brisbane, neither of whom played finals last year, and new side the Dolphins.

"I don't think it's any coincidence that we are seeing teams who were in the bottom half of the ladder (last season) now in the top half of the ladder," he said.

"It may even out again over the course of the season. We have a lot of teams who were expected to be in the eight who may well get there, who at the moment are not in the eight."

South Sydney are one such team - the perennial heavyweights have won one game so far this year but lost their other two by a combined margin of only eight points.

"It's been a pretty good competition so far, there's not really been any blowouts," halfback Lachlan Ilias said.

"I like it, it keeps you on your toes and keeps you honest every week."

Ilias said if the tight nature of the season persisted, teams who could hold their nerve late in games would come up trumps.

"It sort of gives you that extra practice and extra repetition and experience, trying to close out those wins, trying to chase those wins," he said.

"It's good leading into the back end of the year for sure."