As Glenn departs, his Scotland colleague, Andy Craig, the 28-year-old Orrell centre, will be joining Glasgow for next season.
Glenn first sampled rugby in Scotland with Glasgow Accies and was a member of the Glasgow Hawks team that won both the Tennents Premiership Division 2 title and the Tennent's Velvet Cup.
Glenn has played 112 games and scored 27 tries for Glasgow and has played 40 internationals for Scotland, scoring four tries. His international career started and finished against Australia. He made his debut in the 1998 tour match against the Wallabies in Sydney, and his finale in a Scotland jersey was last year's Rugby World Cup quarter-final Australia in Brisbane.
Like many in Scottish rugby, Hugh Campbell, Glasgow's head coach, will be sorry to see Metcalfe’s departure. "Glenn's been outstanding for Glasgow and Scottish rugby. He has been a superb ambassador for rugby, recognised worldwide," the coach remarked in echoing the view of many in Scottish rugby.
"We wish him well for his new venture," the coach added.
"I'm sorry to be leaving Glasgow," said 34-year-old Glenn. "I've been with Glasgow throughout my professional career, and I've thoroughly enjoyed my time here. But I think this is the time to try something different."
He does not yet know where he will be playing next season. "I've got a few options. But I'll wait to see what happens at the end of the French season," Glenn explained.
Craig, the first of Glasgow's newcomers to be confirmed for next season, has played 16 internationals for Scotland. He made his debut against Canada in Vancouver on the 2002 tour to North America, and, most recently, he was in Scotland’s World Cup squad last year, playing against Japan, the United States, and France.
He has yet to sign a contract. "But we've agreed everything in principle,” David Jordan, Glasgow's chief executive, explained today.
Craig was born in St Helens, Merseyside, but he qualifies for Scotland as his maternal grandfather was born in Aberdeen.