The 39-year-old was on target in last month's triumph over Steve Clarke's side and also made the net bulge on Saturday, as Roberto Martinez's men conquered Poland 3-1 to maintain their 100% record in League A Group 1.
Having been taken off with just 63 minutes gone against Poland, Ronaldo should be given the green light for back-to-back starts on Tuesday, although there may be one alteration in the final third.
Martinez may be reluctant to start Pedro Neto twice in the space of four days given his perpetual fitness woes, so Diogo Jota could now join Ronaldo, Rafael Leao and Bruno Fernandes in the attacking quartet.
With Joao Palhinha omitted from the squad on Saturday, Ruben Neves and Bernardo Silva started at the base of the midfield, and that pairing should be seen again from the first whistle in Glasgow.
Even though Antonio Silva offers a more natural presence at centre-back, Chelsea's Renato Veiga - who had never been capped at senior level before this month - began in the middle of the backline against Poland.
The Blues new boy has likely done enough to hold his place at the back, where Diogo Costa, Diogo Dalot, Ruben Dias and Nuno Mendes are primed to join him.
Portugal possible starting lineup:
Costa; Dalot, Dias, Veiga, Mendes; Silva, R. Neves; Jota, Fernandes, Leao; Ronaldo
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