Waerea-Hargreaves sprayed water over Leniu, then threw the water bottle at him after the Panthers forward took exception to him catching rival prop Moses Leota with a cocked elbow in the dying stages of Penrith's 30-6 NRL rout of the Roosters on Saturday night.
When referee Adam Gee opted to also send Leniu to the bin, the irate Penrith player appeared to mouth "car park" to Waerea-Hargreaves before marching up the tunnel at Allianz Stadium, while the Roosters prop was also binned.
On Sunday Waerea-Hargreaves was hit with two grade-one contrary conduct charges worth $3000 each if he takes the early guilty plea.
Leniu was handed the same charges by the NRL's match review committee but his cleaner record means he will only pay $3600 in fines.
While Roosters coach Trent Robinson described the incident as "good theatre" for fans, Panthers coach Ivan Cleary had a very different take.
"It started from Jared. He was just looking for trouble. That was obvious - and he found it," Cleary said.
"(There were) numerous incidents, weren't there? And I think on the balance of probability Jared was probably the one initiating it.
"I don't know, it was a little condescending, I thought. It just was unnecessary."
Cleary also couldn't understand why Leniu was given his marching orders.
"But anyway ... it was probably a good thing in the end, I suppose," he said before admitting he wasn't happy with Waerea-Hargreaves' initial contact on Leota.
"It was very questionable. The way he looked, where he saw him, the way it was cocked," he said.
Robinson enjoyed the contest of two props going after each other..
"It was great wasn't it, for footy? That's why people enjoy watching footy," said the triple premiership-winning mentor.
"There was nothing in it, I don't think, from either end. Like, there wasn't much to it. It was sort of heated there. (But) I don't think Jared did anything wrong in any of (the incidents).
"Guys tried to race out of the line and belt him and that's really unfortunate for Liam (Martin) who copped a hip.
"And then Jared was getting his bumpers up like every guy does in every tackle they run into and copped Moses there. That's a forwards battle.
"And then it flared up. Good theatre. Move on."
Adding to the drama was the sub-plot of Leniu and Waerea-Hargreaves soon to be teammates after the Penrith hard man's decision to defect to Bondi Junction next year.
Robinson doesn't expect any bad blood to linger.
"That's why there was interest there and that's why you get excited," he said.
"You want guys to react like that - and you want those guys in your team."
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