The long-time captain scored the decisive goal in the 90th minute, lashing home from short range to rescue a 1-0 victory after an otherwise drab performance against Iceland.
The minnows had the better of the chances in the first half, despite only sparingly enjoying passages of possession. But they failed to convert on a trio of big opportunities. Still, their rigid 4-4-2 denied the visitors of any big opportunities in the first period.
Meanwhile, Portugal only had sparing moments. Ronaldo made some dangerous runs, but was caught offside more than once. And although the 38-year-old kissed the cross-bar with a header, he was otherwise ineffective in the box. Portugal's most consistent attacking threat was Rafael Leao. The Milan winger's back-post runs stretched the Iceland backline, while his off-ball work made up for the Selecao's immobility through the middle.
Portugal were handed a glimmer of hope when Willum Willumsson was sent off with 10 minutes remaining - and it proved to be crucial. The home side were a player short on a late free kick, allowing Ronaldo to sneak in unmarked at the far post to smash the ball into the net. Although it was originally ruled offside, a lengthy VAR check determined that Goncalo Inacio was onside to nod the ball into Ronaldo's path.
GOAL rates Portugal's players from Laugardalsvollur...