Queensland Maroons coach Billy Slater refused to offer his opinion on a controversial send off for New South Wales Blues debutant Joseph Suaalii during the State of Origin opener, but that didn't stop his captain or New South Wales counterparts from doing so.

Suaalii was sent off in the seventh minute of his Origin debut after hitting Reece Walsh high with direct, forceful contact to the head.

The Roosters' outside back is now facing four weeks on the sideline with an early guilty plea, and his coach suggested the decision to send him off in what ended up as a 38-10 win for the Maroons may have been on the harsher side.

"I think earlier on in the year, he [Walsh] ended up with a broken jaw and there was no send off so it's a big call at this level. The tackle, I mean, he was falling. I'll have to have another look at it, but it was a massive call for a game like this," Michael Maguire said during the post-match press conference.

Maguire said his side played well however given the tough circumstances.

"Playing at this level, playing with 12 [it's hard]. I just spoke to the players there about how hard they wanted to work for each other throughout the game. I thought we put ourselves actually in positions at times where we were quite dominant, but I guess fatigue comes in at some stage," Michael Maguire said during the post-match press conference.

"Playing with a man down though, you have to try and bury the opposition into the corners and at some stage, fatigue finds you. But you know, I'm actually really proud of their efforts. Individuals are out on their feet, so it made it a bit tough, but one thing I do know about this group is that they have shifted the dime on how hard they want to work for the jersey."

Captain Jake Trbojevic had plenty to say on field when referee Ashley Klein made the call to send off Suaalii, and backed that up post-game.

"It was a tough one. I didn't expect him to get sent off if I'm being honest, but that's the way it went," Trbojevic said.

While Queensland coach Billy Slater refused to answer questions around the send off, other than suggesting he will keep his feelings to himself, captain Daly Cherry-Evans said he thought there was nothing to argue about.

"It was pretty standard I reckon. There isn't too much to argue about, it is what it is. The refs are under pressure out there, they made the right decision and as long as Reece is alright, that's the priority out of all of that," Cherry-Evans said.