Sydney Roosters five-eighth Luke Keary turned in another good performance against the Bulldogs.

Queasy Keary quarantined by Roosters

Roosters five-eighth Luke Keary sent a scare through camp on Monday morning when he was sent home from training with a nasty bout of food poisoning, but his teammates are confident he'll be fine to take his place in the halves for Saturday night's preliminary final against the Cowboys.

Keary hasn't missed a game this season and has played an integral role in helping the Tricolours climb from 15th to second on the Telstra Premiership ladder in the space of 12 months.

"I don't know what he ate last night but he's at home on the toilet!" Roosters co-captain Jake Friend told NRL.com.

"Hopefully it's just a 24-hour thing and he'll be back there training to get ready for the weekend."

Teammate Connor Watson saw the lighter side of Keary's situation, revealing it might have been something else that kept the former Rabbitoh away from his side's media opportunity on Monday.

"I think he's just a bit upset that he lost his Fantasy football," Watson joked.

While Keary is a certain starter for Saturday's sudden-death showdown at Allianz Stadium, Watson has put his hand up to fill the void should he be called upon.

The Newcastle-bound utility made the No.6 jersey his own at the backend of the 2016 season and has been solid as a rock wherever coach Trent Robinson has asked him to play. 

"I've been training in those sorts of positions all year and I played a fair bit of five-eighth last year so I'm comfortable playing there and that's where I like playing," he said.

"But I think he'll be alright; he's just a bit crook so he'll be sweet."