Brown has either started or come on in all of Scotland's last 19 Tests

Scotland hooker Fraser Brown will miss the forthcoming autumn internationals after being ruled out for up to eight weeks with a knee injury.

The Glasgow forward, 28, was injured in the Warriors' European Champions Cup defeat at Exeter last Saturday.

Although he does not require surgery, Brown will miss the Tests against Samoa, New Zealand and Australia.

He is the second key player to be ruled out, with captain Greig Laidlaw also missing with a fractured ankle.

"It is a blow for us and Greig," Scotland head coach Gregor Townsend told BBC Radio 5 live. "He was hitting form as well.

"It's been an adjustment for him going to Clermont but it's one of the best clubs in Europe and just to make that adjustment and be able to play well as a scrum-half, at a different club, with a different language - he was doing really well.

"So to miss out in November is disappointing for him and obviously us; he played a huge part in Scotland's success over the past couple of seasons.

"A lot of people look at the on-field stuff and his goal-kicking and his play at scrum-half, but off the field there is so much work that gets done by the players to establish that culture and that drive to get better."

Townsend had better news of stand-in skipper John Barclay, who has been battling against an ongoing concussion issue and has missed his club side Scarlets' last three games.

Barclay has not played since 23 September but is expected to return 'in the next week or two'

Barclay, who took over from the injured Laidlaw mid-way through this year's Six Nations campaign and also led Scotland on their summer tour when Laidlaw was with the British and Irish Lions, saw a specialist at the beginning of the week and is back in training.

"We are fortunate that in John, we have someone there who if available would do a great job," added Townsend, who will announce his squad for the autumn Tests on Monday, 23 October.

"We are hoping John will come back - within the next week or two - to full fitness."

Hooker Brown has been a regular in the Scotland match-day squad for the past three years and has started five of their last eight Tests, including the summer win in Australia.

He only returned to action in late September after undergoing ankle surgery this summer, and will miss half-a-dozen Pro14 matches for Glasgow as well as Saturday's vital Champions Cup clash with Leinster.

Meanwhile Brown's Warriors team-mate, lock Brian Alainu'uese, will also be ruled out for a period of up to eight weeks with a knee injury.