Terry Butcher has urged David Marshall to cement his place as Craig Gordon's understudy in Scotland's friendly against Wales.
Cardiff goalkeeper Marshall, 24, is likely to start at his home stadium on Saturday after Gordon suffered a fractured arm playing for Sunderland on Saturday.
Assistant manager Butcher told the Scottish Football Association's official website: "David has really confirmed himself as Scotland's number two. When you get the opportunity to start the game and play on a regular basis, you've got to grab that opportunity."
Marshall has had some unconvincing performances in a Scotland jersey but was outstanding on his last outing against Holland in September.
He recently expressed his frustration at travelling all the way to Japan for last month's friendly without playing a minute of the game.
Butcher added: "We all know about Craig Gordon and what he can do.
"He's been fantastic for Sunderland, obviously, and unbelievable for Scotland. It is a massive blow for him; he's just come back from an injury as well.
"It does give an opportunity for people like David Marshall and Jamie Langfield to say, 'I want to step up here'.
"David Marshall, particularly, was immense against Holland in the last qualifier, and he's playing on his home ground as well."
