Tuivasa-Sheck was included when the side was originally named for last week's clash against Manly, the 25-year-old was subsequently ruled out with the versatile Peta Hiku again filling the fullback's position.
However, Warriors head coach Stephen Kearney said Tuivasa-Sheck's hopes of playing this week were more encouraging after today's field session.
"He has a few more boxes he needs to tick but he's certainly better than he was last week," he said.
Kearney has listed the same starting line-up initially chosen for the Manly match. Hiku would again be in line to switch to fullback with Gerard Beale coming into the centres should Tuivasa-Sheck be forced to miss the contest on Friday night.
The extended interchange bench includes one change with centre Anthony Gelling added as a replacement for front rower Sam Lisone.
The Warriors remain in fourth spot on 20 points heading into the 15th round, level on points with South Sydney and two behind St George Illawarra and Penrith.
The 9-4 start to the season, the second best in the club's history, contrasts with a grim first half of the campaign for the Cowboys.
They started the year as one of the title favourites after being beaten in the 2017 grand final but have won just four times in 14 matches so far, including only two from seven in Townsville.
Yet their record and the fact they sit 14th in the competition is of no consequence to the Warriors as they contemplate one of their most difficult away assignments.
The overall record between the two clubs is dead even – 19 wins a piece – but it is tilted heavily in the Cowboys' favour at 1300SMILES Stadium (12-5). Of the last 12 matches there since 2002, the Vodafone Warriors have won just once, 20-16 in 2014.
Since starting 2018 with five straight wins, they have had four in their last eight outings with wins following losses.
Wing David Fusitu'a marked his 70th career appearance last Saturday with a hat-trick to take him into an outright lead in this year's NRL try-scoring stakes with 15 in 13 games. He now boasts 47 tries overall giving him a strike rate of a try every 1.48 games.
