Wales must complete a qualifying double over Scotland if they are to keep their World Cup dreams alive, says former goalkeeper Neville Southall.
Chris Coleman's team snatched a 2-1 win when the sides met in October in Cardiff, but they will face a tougher test on Friday against a Scotland side now managed by Gordon Strachan and playing on home soil.
Spurs' Gareth Bale scored a late double to secure the points for Wales in the first encounter and both Southall and former Scotland stopper Alan Rough agree that the winger will have a crucial role to play if he is passed fit for the match.
Scotland are currently bottom of Group A with just two points to their name, but Wales are only one point better off having lost three of their four games.
"I think Wales are under more pressure," Southall, who played for Wales from 1982-97, told Sky Sports News from Hampden Park. "But after what happened in the first game I think the emotion will take the team through. The crowd will be unbelievable - they usually are here.
"I think Chris Coleman is under tremendous pressure because we've got a game on Tuesday [at home to Croatia] and if we don't win here and we're out, there will be nobody at the game on Tuesday and we can't afford that. We need to work hard to get our point here on Friday and push on.
"Bale is the most important player we've got and the most important we've had for ages. But I think Craig Bellamy will be vital for Wales alongside him.
"I watched the pair of them in the Austria game and they made a massive difference. As soon as they went off, the team shape changed and the attacking options dried up.
"So it will be interesting to see if he plays Bale in behind Bellamy of whether he plays Bellamy wide."
Rough, who played in two World Cup qualifier wins over Wales during a career that ran from 1976-86, agrees Bale is a vital player for Wales but believes Scotland are capable of claiming their first win under Strachan on Friday.
"The whole nation is up for this one - I think Gordon has added a wee bit of spice to the game," he said. "All of the supporters coming here will see a new era of Scottish football.
"Gareth Bale is a big, big player for Wales but I think Gordon Strachan has been in the game long enough to know there are another 10 players in the side.
"We've had some fantastic players here, having played France, Italy and Spain and we've coped with their big-time players. I'm sure Gordon has been in the game long enough to know how to deal with him."
Former keepers Southall and Rough, who earned 145 international caps between them, each told Sky Sports News they hold Scotland goalkeeper Alan McGregor in high esteem - both for his talent and his decision to continue learning his trade abroad.
McGregor, 31, signed a two-year contract with Turkish club Besiktas in July and has filled the void left by Craig Gordon, who won 40 caps before bowing out with injury.
"I think we are very fortunate," said Rough. "Alan McGregor has carried on from the great line of goalkeepers we've had.
"Alan has been a bit special. He's moved away and is now plying his trade abroad and I'm sure that will add to his game and, as far as I'm concerned, since he's come into the team he's been the saviour on many occasions."
Neville agreed, saying: "To be fair I do think he's been a terrific goalkeeper. Going abroad into a hostile country like Turkey will do him the world of good.
"For Wales, we haven't got a goalkeeper who is playing regularly in the Premier League, which is a problem for us at the moment.
"Wayne Hennessey was until his injury, but Boas Myhill has come in and done exceptionally well. Hopefully he will be sat on a deckchair on Friday night and we won't need him."
Watch Scotland take on Wales in the 2014 World Cup qualifier at Hampden from 7.30pm on Friday on Sky Sports 2 HD.