Tomos Williams will be assessed after being forced off during the British and Irish Lions' win over Western Force on Saturday.
Williams scored twice as the Lions bounced back from their defeat to Argentina last week. Skipper Dan Sheehan, Garry Ringrose, Joe McCarthy and Alex Mitchell also scored for a much-changed team in Perth.
The scrum-half was among the Lions' star performers at Optus Stadium but his match was over when he injured his left hamstring during the act of finishing his second try in the 47th minute.
Speaking after the game, coach Andy Farrell confirmed the injury, telling Sky Sports: "It's a tight hamstring. You don't know what these things are like. We will assess that."
Lions went ahead inside two minutes only to be immediately pegged back by their hosts. A frantic first half led to a calmer second as the Lions' gulf in class eventually shone through.
Farrell added: "[The game provided] plenty of learning from last week and the same again from this week. When we get out composure in the second half we was able be nice and calm.
"I mean, let's be honest, the Force took it to us. I thought they played a tough high-percentage game. They kept the ball really well and we kept them in good field pos through our ill discipline.
"It was a real good test for us in that first half, glad how we composed ourselves at half-time and kept our composure throughout the second half.
"There are nine new caps there. A couple of lads have not played they will get to play in the next couple of games.
"It is nice to get tries on the board and a few good individual performances. That is all good for the future, and we have to keep pushing one another.
"If you want to look what a Lion should do for his team-mates is when Mack Hansen went up and down the field and fought for his team-mates. That's the sort of spirit we want."
