Newcastle prop Willie Mason faces a month on the sidelines after suffering two separate injuries in a torrid NRL clash with the Sydney Roosters on Sunday.

The veteran forward fractured his cheekbone in three places during the first half of the 28-12 loss and although he played on, left the field just before halftime with a torn calf.

Mason was belted in the face in the 15th minute by the left shoulder of Sonny Bill Williams, who was on Monday charged with a grade-three careless high tackle.

It’s not known whether Mason picked up the facial injury in that collision.

The 33-year-old is expected to have surgery on his cheekbone this week and is set to be sidelined for four weeks.

With six regular-season matches remaining, the news is a big blow to the seventh-placed Knights’ hopes of qualifying for the finals.

The prognosis means Mason should be ready to play in Newcastle’s last two games against Brisbane and Parramatta.