The barnstorming second rower, who has been shrouded in uncertainty during recent weeks following a Round 7 move to the centres, before playing from the bench on Friday, played just a tick over 40 minutes in the loss to the defending premiers.
Fifita was involved in an awkward three man tackle, with his knee buckling back over Isaah Yeo as Dylan Edwards and Nathan Cleary completed the tackle from a higher position than Yeo, who was on the ground at the point of contact.
Concern for David Fifita is right MCL injury by video, contact from tackler causes knee to collapse in. Ability to play on hopefully points to minor sprain (1-3 week return to play) but as we saw with Tom Trbojevic recently - that’s not always the case pic.twitter.com/IHFWQ0XhMb
— NRL PHYSIO (@nrlphysio) April 29, 2022
He was originally able to play through the injury, but was eventually taken from the field and had his knee on ice as he sat on the bench.
Justin Holbrook, in his post-game press conference, confirmed fears were that Fifita had suffered an MCL injury, however, scans will confirm the extent of the damage in the coming days, with a lay off of between one and potentially many more weeks on the cards pending on the nature of the injury.
He sat on the bench during the opening of the Penrith clash, saying he believed the club would need his impact.
"I just thought that we need impact from him. He's not your sort of standard player - he's one that can offer a big impact," Holbrook said.
"So that's why we've not worried about interchanges ... just have him sit out the early part of the game and expect him to be able to play a big part in the back end of the game.
"I thought if he's fit and right, you know, we're a chance."
Fifita only made 64 metres from eight carries in another performance which was well below his best and the incredible levels he displayed on a consistent basis throughout the 2021 season.
Holbrook hinted at leaving Fifita on the bench in coming weeks though.
"I'd rather his 60 minutes be full of quality, rather than get gassed and try and push into 80 [minutes] just for the sake of it," he explained.
"Penrith haven't done it for a few weeks, but they used to always play [Viliame] Kikau for 30 [minutes], then get him off and get him back on, so he'd only play 60 minutes.
"I'd like the luxury of [doing that with Fifita], but then you've got to worry about your middles.
"Tino [Fa'asuamaleaui] played huge minutes for us tonight and that's what puts us under pressure."
The Titans will take on the Sydney Roosters in Mackay next weekend.