The 28-year-old New Zealand Warrior was a late withdrawal from the Kiwis' team for their pre-tournament friendly against the Cook Islands after pulling a groin in training and subsequently sat out both opening fixtures against Samoa and France.
Leuluai, one of five survivors from New Zealand's World Cup-winning team in 2008, was sent earlier this week for scans which cleared him of any major injury and he had his first serious training run at Headingley on Thursday morning.
He was not originally named in the Kiwis' 19-man squad but they have been given permission to make a late change and coach Stephen Kearney is keen to give him an outing before the quarter-finals.
"We've had a bit of a think about Tommy's position and we thought it would be best to give him an opportunity to play tomorrow night, given the importance of next week's game," Kearney told reporters after training in Leeds.
"We took a chance on it. We thought if we give him a chance tomorrow night and see how he pulls up, then at least we'll know where we're at."
Leuluai, who will draw level with captain Simon Mannering as the most-capped Kiwi in the squad if he wins his 31st cap, has in the past been widely used by Kearney from the bench because of his ability to cover both half-back positions and hooker.
"He's a fairly versatile member of the team," said the coach. "We can use him in a number of positions."
Kearney will wait to see how Leuluai recovers from his first training session for over a week before finalising his line-up and says he may even wait until an hour before kick-off.
"If he's not in good shape tomorrow morning, then I'm not going to play him," Kearney added.
"But I'm pretty confident. He moved alright and he feels confident which is really important.
"We've been given confirmation that we'll be able to drop our 19th man off, which was Simon (Mannering) and bring Tommy in in his place.
"If he pulls up okay, then he'll come into the 17 and Greg Eastwood will drop off the bench."
Stand-off Kieran Foran, who will captain the side for the second time in the absence of the rested Mannering, is keen to see the experienced Leuluai back in the side.
"It's a huge boost," said Foran. "It just depends on how he pulls up from the training session. If he's pulled up well, then he'll find himself in the team.
"I don't really know what sort of role Tommy is going to play when he comes into the side but it's a big asset to have him back."
The holders are guaranteed a place in the last eight following emphatic wins over Samoa and France, and Kearney is urging his players not to underestimate the Kumuls, who need to pull off an unlikely victory to keep alive their slender qualification hopes.
"It's really important that we keep our focus," he said. "There are a couple of areas of improvement from last week.
"I'm not too sure how the Kumuls will turn up but what I can guarantee is that they'll play with a lot of passion and a lot of spirit. We have to be well aware of that."
Papua New Guinea coach Adrian Lam is looking for his players to regain their pride following disappointing performances so far and insists Friday's game is not a foregone conclusion.
"I know a lot of the press are talking about damage limitation but we haven't given up," Lam said. "Anything can happen in any game.
"They are the world champions, they've stuffed France and Samoa and we're the next in line.
"But we've spoken to the guys about courage, character and pride and we feel we can acquit ourselves with pride.
"We've questioned the guys' character and we'll see if we get a response.
"There will be some new faces getting a run and we're looking for some enthusiasm from them."
The Kumuls lost Isreal Eliab and Larsen Marabe to injury in Monday's 38-4 defeat by Samoa and Lam will give debuts to prop Joe Bruno and three-quarter Francis Paniu, from the Rabaul Gurias, and a second cap to Port Moresby second rower Sebastian Pandia, another player from the country's domestic competition.
Lam has come under fierce criticism back home, where rugby league is the national sport, but will resist the inevitable calls for his resignation and has promised to front the media on his return to Papua New Guinea.
"I'll deal with that when I get home," he said. "We've a lot of work to do before then."
- Sports & Recreation
- Stephen Kearney