Roosters coach Trent Robinson loved the fire he saw from Spencer Leniu on Friday night but reminded his enforcer in the middle that he needs to regulate his aggression to ensure it doesn’t cost them in the finals.

There were emotional scenes before the game against South Sydney as both sides and their supporters came together to celebrate Jai Arrow’s 100th game for the Rabbitohs.

But the pleasantries were never going to last between the biggest NRL rivals, with Leniu and Rabbitohs forward Keaon Koloamatangi coming together midway through the first half.

Koloamatangi put on a big shot from the kick-off and let Leniu know about it, with the pair clashing later in the set near halfway.

The Roosters were awarded a set restart which led to Leniu getting in his rival’s face which sparked a melee. Things appeared to have cooled down, only for Leniu to fire up again which saw referee Adam Gee reverse the penalty.

Friday’s game didn’t mean much for the Roosters who were always going to finish fourth, but a similar penalty could be costly in the finals.

“(He flirted with the line) and he went over it, and I want him to play with his natural spirit and just stay under the line,” Robinson said after the game.

“We spoke about that, and I’ll encourage him to be himself and take on the opposition, and then he’s got enough experience that he just should have regulated that and played the ball.

“But after that, what did he do wrong?

“He creates an atmosphere when he’s in that mode. Other than that, I would have liked it to be beneficial for us.”

Leniu came off after 30 minutes and copped it deluxe from Souths fans, with the fiery forward giving it straight back to them as they hurled abuse while he was on the exercise bike.

There was terrific theatre in the final few minutes as the crowd roared when Latrell Mitchell was shown on the big screen, only for them to boo Leniu when they showed him on the bench.

Robinson didn’t bring the Samoan star back on in the second half but explained it was purely so his youngsters could get a taste of first grade on the biggest stage.

“I think it was good for the fans, a good spectacle leading into the finals,” Koloamatangi said afterwards.

“We were teammates in Origin. We spoke about it after the game and had a laugh about it so we’ll leave it on the field and we’re sweet.

“He’s the enemy (when we’re not playing together). He’s not on my side, so whoever’s not on my side is the enemy. I won’t back down to anyone, but after the game we laughed about it and moved on.”

Souths veteran Cody Walker enjoyed the fiery exchange on a night his side sealed a home final next week, with Rabbitohs fans relieved Mitchell’s monster shot on Toby Rodwell didn’t creep up high in the dying stages.

“I think with the whole rivalry, it’s not a Roosters and Souths game without a bit of that feel and oomph,” he said.

“I thought Keaon handled himself quite well and gave us a penalty. You’ve got to expect those things when you’re coming up against two arch-rivals. They go at each other on the field and leave it there.”

Originally published as ‘He’s the enemy’: Trent Robinson loved Spencer Leniu’s aggression on Friday night, but it’s a balancing act going into the finals