Bath will play a waiting game for as long as it takes regarding England flanker Sam Underhill's return to rugby.
The 21-year-old, one of English rugby's most exciting prospects, has not played since being concussed when England beat Australia four weeks ago.
It was his second injury of that type this season, having been hurt during Bath's Aviva Premiership game against Northampton in September.
And he remains sidelined as his club move into three Premiership rounds either side of Christmas, which is followed by their two remaining European Champions Cup pool matches.
"He is still really symptomatic," Bath rugby director Todd Blackadder said, following his team's 26-21 victory over three-time European champions Toulon.
"On Tuesday he still had symptoms of what happened to him playing for England. It is one of those really frustrating ones.
"We want him out there as soon as we can, but when a player has got the symptoms that he's had, it puts it back another week.
"He is just not feeling quite right. We put him under some physical exposure, and he's just not feeling 100 per cent. We have specialists here, and it is symptomatic of concussion. It is one of those things you have to deal with.
"You have to trust the process and that the specialists will make the right calls. We would never put a player in danger, you just have to wait and see.
"Hopefully, we cross our fingers and he comes right. Player safety these days, it is really important we get it right.
"Even for the players it can create an anxiety for them. They have to think about their careers and what happens if it all finishes now."
Blackadder, meanwhile, confirmed that Wales number eight Taulupe Faletau does not require surgery to rectify a knee injury he suffered against Toulon in France eight days ago.
"It doesn't need surgical intervention, which is a real positive," he added. "That cuts it back by about a month. We are looking at about 12 weeks."
The latest bulletin on Faletau could mean him being available for Wales' final two Six Nations games against Italy and France in March, but he is set to miss appointments with Scotland, England and Ireland.
Wales head coach Warren Gatland has already lost two of Faletau's fellow 2017 British & Irish Lions -- flanker Sam Warburton and centre Jonathan Davies -- from his Six Nations plans through injury.
Bath top their European pool on points difference in a race for quarter-final places and they should progress if they beat a dangerous Scarlets outfit next month, followed by Benetton in Italy.
"I think it is a massive mindset shift for us that we can trust ourselves to front-up against anyone," Blackadder said. "It [Toulon victory] was more than a win -- it was a psychological win.
"We trusted our defence, we trusted our attack and it is creating opportunities. I think we will really grow from this. There is more to come."