BEN Hinshelwood has been ruled out of Worcester Warriors' trip to Saracens.

The Sixways club captain has struggled to train all week because of back spasms so Tommy Hayes comes in for the Scotland international at centre.

Worcester will also have a revamped front row for Sunday's Premiership clash at Vicarage Road (3pm) with Steve Sparks and Colin Noon drafted in.

Worcester's director of rugby John Brain is an admirer of the Saracens pack and believes that Sparks -- a recruit from Sarries in the summer -- will have the inside track on their front row.

"Steve knows their props inside out," said Brain. "That can only help us because the scrum will be a key battle on Sunday.

"Cobus Visagie is one of the top three scrummagers in world and I think the battle between him and Steve will be a very, very interesting one for connoisseurs of rugby.

"Steve made a career decision in the summer to come to Worcester although I think Saracens would have been quite happy to keep him. He will be very much up for the game against his old club."

"Saracens have quality all over but, if you look at their pack, it is a who's who of international rugby."

Worcester's preparation for the game has been hindered by injury concerns over Hinshelwood, Neil Lyman (sternum) and Tony Windo (head) and all three are ruled out of the starting line-up.

"Ben is getting better," added Brain. "However, he hasn't trained all week and, in Tommy Hayes, we have a very experienced man who is comfortable at centre and also gives us kicking options."

South African hooker Andre Van Niekerk is named in the 22 for the first time after missing last Sunday's opening-day defeat to Newcastle Falcons but fellow new signing Clive Stuart-Smith is out of the squad with Matt Powell on the bench.

Team: O'Leary; Gollings, Hayes, Tr-ueman, Lombard; Brown, Cole; Spar-ks, Daly, Noon, Collier, Gillies, Greeff, Sanderson, Hickey. Reps: Windo, Van Niekerk, Fortey, MacLeod-Henderson, Murphy, Powell, Delport.