© Stu Forster/Getty Images

England centre Manu Tuilagi will make his first start for 15 months when Leicester tackle European Champions Cup opponents Treviso on Saturday.

But while Tuilagi and England hooker Dylan Hartley are both in action -- Hartley missed last weekend's Aviva Premiership clash between Northampton and Leicester because of a rib injury -- Wasps forwards Joe Launchbury and James Haskell are absent from their club's Champions Cup appointment with Toulon on Sunday.

All four players were named in Eddie Jones' elite player squad earlier this week ahead of next month's Six Nations Championship.

Tuilagi, who has not played Test rugby since June 2014, made his comeback as a second-half substitute last Saturday, featuring for just over 25 minutes when Tigers beat Saints 30-27.

And club action is set to be his immediate priority as he looks to build full match fitness ahead of possibly featuring for England later in the Six Nations tournament.

Hartley, meanwhile, starts for Northampton against Franklin's Gardens visitors Glasgow on Sunday, but lock Launchbury (concussion) and flanker Haskell (shoulder) miss Wasps' trip to Stade Felix-Mayol.

Wasps rugby director Dai Young though has delivered an upbeat assessment about both players,with Haskell expected to be fit to face Ricoh Arena visitors Leinster next week and Launchbury also firmly on course.

"We are confident James Haskell will be back fit for next weekend," Young said. "It's a knock rather than a serious injury, but illness has prevented him from getting treatment on it this week.

"We are also comfortable that Joe Launchbury will have cleared all concussion protocols by this weekend, but he wouldn't have been ready to play Toulon.

"Even if he has passed all protocols, he has still taken a couple of big bangs and it would be irresponsible to play him, so we won't take that risk."

England kick off their Six Nations campaign against Scotland at Murrayfield on Feb. 6.