Liverpool goalkeeper Pepe Reina says Spain must be wary of teammate Charlie Adam when they face Scotland tonight.
Scotland need victory to reach the European Championships.
Reina said: "My preference would be for the Scots to go through because of Charlie, the manager, Steve Clarke and young Danny Wilson.
"Charlie will be crucial to Scotland in Alicante - he is one of the best players in their team.
"If they want to do something big then he holds the key."