Wyong's semi-finals hopes were dented by the result.

To compound the problem, their captain and chief playmaker Mitch Williams dislocated his elbow and was forced from the field early in the second half.

Elbow dislocations can be season-ending - particularly when there are just five matches before the semi-finals.

X-rays cleared Williams of broken bones but Wyong football manager Matt Lavin said that the hooker might well have played his last game for the season.

Wyong led 12-10 at the break but were impatient and untidy in a second half that saw Newcastle dine out on the Roos' errors.

Wyong created plenty of scoring chances in the first stanza, but their finishing was often frantic and undisciplined.

The loss of Williams early in the second half took the zip out of the home team's attack.

Meanwhile, the Knights kicked well and strangled Wyong out of the contest.

Lavin said Williams' value to the Roos was highlighted in the first half when he teased the Knights' left-edge from dummy-half and looked to pass out the back but sent the ball to lead runner Vaha Pulu angling in at the space between defenders.

"The pass was timed to perfection. Pulu split the line then stepped around fullback Braydon Williame to score and Wyong went to halftime with a 12-10 lead," Lavin said.

In the second half Wyong lost patience and overplayed their hand too often, he said.

"This was a very professional performance by the Knights. Wyong engineered as many opportunities as Newcastle but the difference lay in the execution," he said.

"The Wyong kicking game was substandard and the attack lacked patience."

■ Wyong will take on Wentworthville at Cronulla this Saturday in a match that will be televised live on Fox Sports from 10.40am.