Wales coach Warren Gatland may be dealt another major injury blow ahead of his team's autumn Test series opener against New Zealand.
With less than three weeks to go before Wales face the All Blacks, Gatland is now sweating on British and Irish Lions scrum-half Mike Phillips' fitness.
Gatland has already lost Phillips' fellow Lions Lee Byrne (foot) and Adam Jones (shoulder) from his November plans, in addition to prop John Yapp (torn biceps) and lock Ian Evans (torn tendon).
Phillips became the latest concern when he limped off before half-time in the Ospreys' 25-24 Heineken Cup victory over Clermont Auvergne.
Gatland was among the Liberty Stadium crowd that saw Phillips depart. He appeared to be hurt during build-up play to the Ospreys' second try.
The Swansea-based side raced into a 19-point lead - they headed Pool Three opponents Leicester by 18 points last weekend before being held to a draw - and then found themselves hanging on despite tries from Tommy Bowe, Ryan Jones and Barry Davies.
"Clearly, it was nerve-wracking, and we were just glad to get over the line," said Ospreys coach Sean Holley.
"We knew at half-time that they would come back at us, and they did that, but we did extremely well and showed some resolve to get back in front at the end.
"Like last week, we probably should have pushed on and got the bonus point, but we are in a good position in the group."
Bath head coach Steve Meehan admits it will take "a really good effort" for Bath to reach this season's Heineken Cup quarter-finals.
The west country club suffered a shattering 29-27 home defeat against French giants Stade Francais.
Scrum-half Julien Dupuy's seventh penalty a minute from time condemned Bath to their second successive Pool Four defeat.
No team has ever reached the Heineken quarter-finals after losing their opening two group games, but that is the colossal challenge now facing Bath.
Dupuy, meanwhile, dumped Bath out of last season's tournament, scoring a dramatic late try for his old club Leicester in a quarter-final clash.
"We are going to have to play very well in our remaining four games and hope other results go our way," admitted Meehan, after Stade prevailed despite Bath tries by Nicky Little and Matt Carraro.
"I won't be too hard on the players. It is obviously very disappointing for all of the guys.
"Unfortunately, we were penalised a couple of times too often, and perhaps we went away a little from how we played in the first-half.
"But we played a much better brand of rugby than we did against Ulster last week, and we will continue to try to develop that."
Bath wing Matt Banahan had earlier run riot after the 6ft 7in powerhouse repeatedly blasted through Stade's defence.
His line-breaking prowess from broken field play was showcased spectacularly as he warmed up for England's autumn Test series that starts against Australia on November 7.
But Stade's triumph continued a profitable weekend for French clubs against English opposition, following victories for Perpignan, Biarritz and Toulouse over Northampton, Gloucester and Harlequins.