Newman is facing around a month on the sidelines after suffering a recurrence of his hamstring injury.
The England World Cup hopeful missed Rhinos’ first four games of the season after damaging a hamstring in Tom Briscoe’s testimonial game against Hull on January 30.
He returned in the win at Wakefield Trinity a week ago, but the injury struck again and Newman will miss Thursday's visit of Hull.
Coach Richard Agar confirmed: “We have got some further tests going on.
“It is disappointing. We could not have been much more careful, we had it scanned, fully healed and we kept him back for extra time to get some more miles in his legs.
“We are looking at similar time frames to last time, but obviously [we will be] ultra-careful.”
Rhinos are also without Kruise Leeming and Cameron Smith who will both serve a one-match ban tonight.
Muizz Mustapha has been drafted into the squad for the first time since 2020 and Liam Tindall and Jarrod O’Connor could play after featuring on dual-registration for Bradford Bulls last week.
Alex Mellor (concussion) is back in contention and Jack Broadbent, James Donaldson and Corey Johnson are vying for a call-up.
Hull are without Josh Reynolds (fractured elbow) and Jordan Lane (back) who were both injured during last Sunday’s defeat at Castleford Tigers and Connor Wynne (arm) is a fitness doubt.
Former Rhinos captain Luke Gale continues his suspension and Darnell McIntosh, Carlos Tuimavave, Manu Ma’u, Cameron Scott, Scott Taylor and Jacob Hookem remain on the casualty list.
Joe Cator could feature for the first time since suffering an Achilles injury last August.
Rhinos from: Walker, Fusitu’a, Sutcliffe, Handley, Austin, Sezer, Oledzki, Prior, Martin, Tetevano, Dwyer, Mellor, Thompson, Briscoe, Gannon, Broadbent, O’Connor, Donaldson, Johnson, Mustapha, Tindall.
Hull: from Connor, Swift, Griffin, Sao, Houghton, Satae, Savelio, Lovodua, Cator, Evans, Fash, McNamara, Brown, Johnstone, Bowden, Wynne, Vulikijapani, Burrell, Shaul, Severs, Barron.
Referee: Liam Moore (Wigan).
Kick-off: Thursday, 8pm.
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