Rugby:Ulster captain Johann Muller is expected to be out for up to eight weeks after undergoing surgery on a thumb injury picked up in the province's victory over Glasgow on Friday night.

The 32-year-old South African secondrow underwent a scan after the game that revealed he had ruptured the ligaments around the thumb and he was operated on Sunday.

The former Springbok captain has been a mainstay of the Ulster side since his arrival in Belfast in 2010.

Under his leadership, Ulster are unbeaten this year in both the Pro12 and Heineken Cup campaigns.