A war of attrition, a typical cup tie, call it what you will - this was a difficult match to watch. But Portugal and their captain found a way through the muddy waters.
He was isolated, almost ignored at times by team-mates, but this was a very different Ronaldo. He handed over free-kick duties and won defensive headers before giving his side the victory with a point-blank miss. Portugal's captain, at last, took one for the team in Lens.
It was billed as the best of the early last-16 ties, certainly on paper, but Lens had been lulled into apathy by half-time. No shots on target in 90 minutes - a tournament first, of course - underlined a match desperately short not only on quality, but attacking intent of any kind.
It got so bad that Croatia fans exploded into song just two minutes before half-time, either through sheer relief that the break was imminent, or simply to give themselves something to do.
Croatia edged the chances, scarce as they were. A fine move involving Ivan Rakitic and and Ivan Strinic forced a corner that resulted in Ivan Perisic shooting narrowly over the bar.
Domagoj Vida missed three good openings from crosses, but an imposing quartet of fit-again Luka Modric, Rakitic, Marcelo Brozovic and Perisic looked a shadow of the one that haunted Spain on matchday three.
Portugal defended stoutly, with Jose Fonte particularly impressive, but a renewed solidity did little to mask a startling lack of precision in an attack. That Ronaldo did not have a shot before the 117th minute tells its own sorry tale - but when he finally did hit the target, it made all the difference.
There was a moment during the warm-up when, while taking part in sprint drills, Ronaldo became completely absorbed in watching two team-mates messing about with the ball. Like a dog told furiously to 'leave it', his eagerness to run over and get involved was palpable.
Portugal made almost no attempt to harness that incorrigible desire to be the main man. Ronaldo's hold-up play was better than it had been so far in these finals, but maligned as he has been for his histrionics in France, it was hard not to feel a little sorry for him as his team-mates ignored runs and passed sideways at will, while he did more than his fair share in his own penalty area.
Their fans deserve a mention - songs and drumbeats persisted for the whole 120 minutes - and they got their reward when substitute Ricardo Quaresma turned home right in front of them, moments after Ivan Perisic had headed against the post.
Ronaldo, far from lament his shot being saved, wheeled away in celebration. This one, at least, was for the team.
Croatia, celebrating Statehood Day, will consider this a missed opportunity against a team who shipped three goals to Hungary. Captain Darijo Srna's tears at the end of a tournament during which he lost his father felt extraordinarily poignant, but Portugal can now look forward to a quarter-final against Poland, and it can only get better from here.