Bath loose-forward Taulupe Faletau left the field after 12 minutes in their game against Northampton Saints because of a possible injury.
Faletau might have damaged his knee ligament and had to leave the field early during his side's 18-14 win and it is still unclear how long he will be out for.
Bath coach Todd Blackadder says that the loss of the Welsh international showed the depth of his squad.
"It sounds like a little bit of a medial, so we'll just wait and see," Blackadder told the BBC.
"It's about the strength in depth of your whole squad and we showed that."