Connacht outhalf Miah Nikora could be out of action for up to five months due to a shoulder injury.
It was confirmed yesterday that New Zealander Nikora will require surgery.
Head Coach Pat Lam said: "Miah's news is a big blow to us. We don't have someone of his experience alongside Dan Parks, but we have to move on and give the other guys an opportunity."
Elsewhere, Craig Clarke returned to training yesterday and will continue to be monitored in today's session to assess his availability for this weekend.
Denis Buckley and Tadhg Leader were also back to full training at the start of this week.
Galway-man Eoin McKeon remains on the injury list with an ankle sprain and will undergo a scan this week for further review.