Injured Panthers forward Trent Merrin.

Trent Merrin has undergone surgery on a fractured finger in Penrith's Nepean Hospital on Sunday as the Panthers' injury woes deepen following their 26-20 loss to the Cowboys.

The Panthers have showed enough courage in 2018 to not let setbacks slow them down but even they couldn't pull this one off after losing Merrin before kick off and slumping to a 20-0 deficit in the first half in front of a record-breaking crowd in Bathurst.

Merrin's freak finger fracture in the warm-up, when he clashed with Sione Katoa in a contact drill, capped off a horror nine weeks for the Panthers, whose casualty ward includes Nathan Cleary, Waqa Blake, Dylan Edwards and Josh Mansour.

Coach Anthony Griffin initially said Orange hospital had been booked for Merrin to have the finger operated on as soon as possible. 

But a last-minute change of plans saw Merrin jump in a car with club officials and drive back to Penrith, where he was admitted to hospital on Saturday. 

A club spokesman said it would depend on what surgeons find as to how long the former Test back-rower was kept on the sidelines.

It seems likely though that Griffin will need to blood a new player - the Panthers' fifth in 10 rounds - for Newcastle next weekend as on top of Merrin, forward Jack Hetherington is facing at least one week out for a dangerous contact charge on Cowboys' Shaun Fensom.

That debutant is probably 21-year-old Nick Lui-Toso as he is the only prop forward left in the club's top-30.

"It's certainly a lot of injuries but we had a team out there tonight that was capable of winning that game," Griffin said.

X-ray of Trent Merrin's injured right finger
X-ray of Trent Merrin's injured right finger

The coach indicated no players were due back next week and lamented the poor start to the Carrington Park clash.

Penrith conceded three tries and had Dallin Watene-Zelezniak sent to the sin bin for striking in a nightmare opening 40 minutes.

"There was lots of courage but we just put ourselves in a position where it was always going to be hard," Griffin said.

"That first half we couldn't have done any more to them to hand it over to them in the first 30-35 minutes.

"The opposition are quality and they were slick at the start. We couldn't control that or have our line speed to them. They pulled us apart."

Penrith skipper Peter Wallace agreed the game was lost early, but he was proud of the effort to rally back to 24-20 with 20 minutes to play.

"I thought momentum of the game showed on the scoreboard," he said.

"The first half they had all the momentum. The second half we got some back and scored a few tries, then gave them a few leg-ups and it turned the momentum back to them.

"It stopped our comeback. But like Hook said we just can't be starting a game like that, giving away a 20 points head start."