Bristol Bears star summer signing Charles Piutau has been ruled out for four weeks with a calf injury meaning he'll miss the European Challenge Cup quarter-final in La Rochelle and at least three Premierships matches, including The Clash against Bath at Twickenham.
Bristol have lost their most explosive and dynamic attacking player at a crucial stage of the season after the New Zealand international limped off against Northampton on February 23 in the first half.
The Bears have carefully managed information coming out of Ashton Gate surrounding his fitness with coach Pat Lam confirming on Tuesday he would be assessed 24 hours before Saturday's crucial game against Worcester.
It is the third major injury Piutau, 27, has sustained since arriving in the West Country last summer from Ulster and has limited his impact for his new team.
Piutau injured his shoulder in the club's final pre-season game against Connacht which saw him miss the first two months of the season and he then picked up a hamstring injury at the turn of the year. In total he has played nine of a possible 26 games, scoring four tries.
It's a cruel blow for head coach Lam who, although insists he has the strength and depth to manage such injuries, would dearly love such a game-changer at this stage of the campaign.
Back-to-back victories have eased any lingering relegation fears and Bristol can now start to look up the table towards the European places with sixth-placed Bath within striking distance.
The Bears travel to Stade Marcel-Deflandre for their European quarter-final on March 31 and their remaining six league fixtures feature trips to Leicester and Bristol, home games against Worcester, Saracens and Sale plus the showpiece derby against Bath on April 6.
At best, Piutau will be fit for the away game against Leicester plus the Sale and Newcastle fixtures in May.
In his place, Luke Daniels will start at full-back against Worcester in five changes from the starting XV which beat Northampton 26-24. Second row Ed Holmes returns from an ankle injury while Tom Pincus and Harry Randall come into the backline and Jake Woolmore and Lewis Thiede form a re-jigged front row.
Bears are hunting their third-straight league victory with Lam admitting his team has learned from the reverse fixture in October where he side were completely over-powered and thrashed 52-7.
"That's the one game I'm really thankful for because that's the game the whole club, the current members, that went through that adversity together that gave us the excitement," Lam said.
"I'd never change that game because we wouldn't be able to accelerate as we have if we hadn't had that game. It was a blessing, without a doubt.
"All I can say is that we are better than when we were when we played these guys first time. It gives us a great opportunity to get success."
Bristol Bears: 15. Luke Daniels; 14. Luke Morahan, 13. Piers O’Conor, 12. Siale Piutau (co-capt), 11. Tom Pincus; 10. Callum Sheedy, 9. Harry Randall; 1. Jake Woolmore, 2. Harry Thacker, 3. Lewis Thiede, 4. Ed Holmes, 5. Chris Vui, 6. Steve Luatua, 7. Jake Heenan, 8. Jordan Crane (co-capt)
Replacements: 16. Sam Parry, 17. Yann Thomas, 18. John Afoa, 19. Joe Batley, 20. Dan Thomas, 21. Andy Uren, 22. Ian Madigan, 23. Mat Protheroe
