This was a Scotland performance with a mix of class in the first half, and sheer guts and concentration in the second period.
Clarke opted to give Bologna’s Lewis Ferguson a rare start alongside John McGinn and McTominay, with Kenny McLean and Billy Gilmour tucked in behind them.
It worked brilliantly as the midfield made a confident start, knocking the ball about and slowly opening Greece up as the half wore on as they combined quickly to move up the pitch.
The penalty was perhaps dubious, but it was earned amid growing Scotland pressure and McTominay, so often Scotland’s hero, confidently tucked it away.
After the break, though, it was about clinging on.
Grant Hanley and John Souttar were outstanding at the back, the latter making a crucial block to deny Tzolis, but Clarke will be slightly concerned with just how drastically the momentum changed.
Greece had 18 shots in the second half alone, with Scotland registering just a single effort – McGinn’s strike from 25 yards.
It is a warning ahead of the Hampden return that Greece will not go away easily, but with a lead and home advantage Scotland are in a strong position.