A place in history is at stake as the national side attempt to qualify for the knock-out phase of a major tournament for the first time ever.
Scotland will progress to the last 16 if they claim the three points in their final Group D fixture, which will be easier said than done againt a Croatia side who were World Cup runners-up only three years ago.
Clarke’s biggest selection dilemma centred around replacing Billy Gilmour, a stand-out in the 0-0 draw at Wembley on Friday, who is ruled out after being placed into self-isolation following a positive Covid test on Monday.
Here is the starting XI he has selected for the biggest match the country has faced in decades ...
1. GK - David Marshall
The Scotland goalkeeper was solid at Wembley after being caught out by the Czech Republic. Another clean sheet tonight would go a long way towards securing qualification for the last 16. Photo: Stu Forster
2. DCR - Scott McTominay
Steve Clarke's swiss army knife reverted to right side of the back three at Wembley after starting in midfield against the Czechs. His impressive performance against England ensures he starts in defence again tonight. Photo: Justin Tallis - Pool
3. DC - Grant Hanley
Defensive centre-point has been reliably solid in both games - and particularly stood out at Wembley. No nonsense at the back is the sort of attitude Steve Clarke needs in his role in the central three, and the Dumfries man delivers. Photo: FRANK AUGSTEIN
4. DCL - Kieran Tierney
Made such a difference to the side at Wembley after missing the tournament opener - and he will be vital to Scotland's hopes again tonight. His driving runs from defence can cause Croatia problems. Photo: ANDY BUCHANAN