Glasgow Warriors forwards Jack Dempsey, Max Williamson and Gregor Brown have all dropped out of the Scotland squad as Gregor Townsend's side prepare to face Portugal on Saturday.

Club-mate Johnny Matthews and Scarlets prop Alex Hepburn have been called up as replacements.

Number eight Dempsey picked up a shoulder injury after starting Sunday's defeat by South Africa.

Lock Williamson suffered a hand injury after coming on as an early replacement following Scott Cummings' red card, while flanker Brown, who did not feature at Murrayfield, has a rib injury.

Hooker Matthews, who has one Scotland cap, was a surprise absentee from Townsend's original squad following fine try-scoring form for his club.

Fellow 31-year-old Hepburn has four caps.

Portugal visit Murrayfield on Saturday in the second of Scotland's Autumn Series internationals, which conclude with the visit of Australia on 24 November.