Brian McDermott was left frustrated with prop Mitch Garbutt following his red card in the World Club Series defeat to North Queensland Cowboys.
Garbutt was dismissed late on for a ferocious punch on James Tamou in the 38-4 defeat to the Cowboys, with Tamou getting sent to the sin-bin.
He is now likely to serve a suspension, which only increases an already problematic situation for McDermott with seven first-team players already out through injury.
And McDermott had no qualms with his dismissal.
“There’s some provocation but not enough,” he told the Yorkshire Evening Post.
“It was silly from Mitch. He was very passionate in the second half – a lot of our players got a bit frustrated – but it was silly from him.
“It didn’t justify that. I’m sure Keith can handle being slapped.”