Newcastle Knights coach Adam O'Brien has empathised with his club's fans after loud boos rang around McDonald Jones Stadium following the conclusion of a narrow 22-20 loss to the Sydney Roosters in the opening contest of Round 6.

Looking to back up last weekend's home win over the St George Illawarra Dragons, the Knights came up just short against the tri-colours in a topsy-turvy contest.

It was a match that wasn't also without its controversy, with the match officials team - led by referee Gerard Sutton - booed off the ground by the home fans after the full time siren.

McDonald Jones
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That was sparked by a late non-call, with the Knights in attack and looking for a chance to either tie or win the game.

It had appeared that, after making a break, there had been a second effort on Kalyn Ponga from Junior Pauga which would have led to a penalty and a difficult attempt at penalty goal to tie the game and send the contest to golden point, but no call came from referee Sutton.

O'Brien suggested the decision should have been a "clear" penalty, but also took frustration with the way the ruck was policed all night, citing inconsistency between the two teams.

“I empathise, these fans, they know footy. I don't think I've heard a stadium so frustrated, never heard booing like that at the end of a game so there must be something in it,” O'Brien said during his post-match press conference.

“Obviously the Kalyn one at the end stands out, you'd like to think that (is penalised) as a professional foul, sin bin, and we kick the goal… I think it was pretty clear, that one.

“With the ruck speed, it just felt like there were two different standards there. Not taking anything away from them, they work hard at their defence and stack really well, but just felt like we didn't get many rewards.”

Unsurprisingly, Roosters' coach Trent Robinson disagreed with O'Brien's version of events, but wouldn't elaborate beyond a one-word answer of "no".

Despite O'Brien's criticism, the Knights won the penalty count 6-4, while the set restart count was locked up at three a piece.