Penrith winger David Simmons will undergo scans on Monday to determine the extent of a hamstring injury suffered in Saturday night’s 24-4 NRL defeat to the Roosters.

Simmons, 30, came off midway through the first half and failed to return.

With Josh Mansour (knee), George Jennings (leg), Jamal Idris (ACL), and Matt Moylan (ankle) also on the sidelines, the Panthers will be sweating on a positive outcome.

“He had a bit of a hamstring issue and he was at a stage where he basically felt it was going to go,” coach Ivan Cleary said after the game.

“I guess the good news is he didn’t play on and make it worse.”

But while the squad is facing a backline crisis, hooker James Segeyaro is inching towards a return from his knee injury.

The Panthers have missed the dynamic play from their star No.9, who hasn’t played since tearing his medial against Canterbury in Round 15.

“[Segeyaro] is close but not exactly sure if it’ll be next week or the one after,” Cleary said.

“That hasn’t been an issue for us though. We had 17 fit guys out there who were beaten by a better team.”

Cleary accused his side of not turning up mentally prepared to take on a Roosters side that dominated the middle third.

Four Roosters forwards – led by prop Jared Warea-Hargeaves – cracked the 100-metre mark as their bigger pack exposed a frail Panthers midfield.

“It was pretty much one way traffic,” Cleary said.

“We couldn’t contain their go forward and I was disappointed with our defence too. I thought it just wasn’t up to it.

“We looked the best on our goal-line but it was just a bit too easy to get down there.

“We probably didn’t turn up with the right attitude defensively and once they got a sniff they were very hard to stop – they’re a very powerful team.”