SAINTS will be forced into two changes in their starting pack when they return to Super League action against Wakefield Trinity at the Totally Wicked Stadium on Friday.

Neither Matty Lees or Sioni Mata'utia are to figure following the injuries they sustained against Leeds Rhinos in the Challenge Cup third-round win against Leeds Rhinos on Saturday.

Both left the field in the opening 10 minutes, with Lees' ankle injury leaving him sidelined for a spell.

“Matty Lees is going to be out for a few weeks,|" said Saints head coack Kristian Woolf.

"We’ve got to get a few more scans to figure out exactly what we’re doing going forward, but he’s definitely going to be out for a little while."

Mata'utia exited play with a head injury and Woolf chose not to put him back into the action against Leeds.

“Sione pulled up really well. He actually passed all his concussion tests on the weekend and we made a decision not to put him back out on the field," he said.

"He’s recovered really well, but at this stage he won’t play this weekend. We’re going to make sure we look after him and that he’ll be right to go again the following week.

“We need to follow the protocols but I’ve said a number of times that we want to make sure we look after our players.”

Woolf has named three players who are in the mix to come into the 17 instead.

“With change you get some opportunity. And a couple of young blokes will get opportunities to bring some real energy and really get an opportunity to cement their spots in the squad," said Woolf.

“We haven’t finalised exactly what we’re going to do with the team just yet, but there’s certainly going to be some fresh faces and I’m looking forward to seeing what they bring.

“There’s a number of guys in the mix, players like Jake Wingfield, Joe Batchelor, big Dan Norman.

“They did a really good job through the trials and have all shown some great improvements through the pre-season and what they’ve done around training so far.

“I think all three of those guys, given the opportunity, would come in and want to make an impact and want to bring some real energy to the squad."