With a World Cup place secured, Croatia manager Zlatko Dalić made seven changes to his starting lineup for this final Group L game, while Montenegro had only pride at stake.
One of the players to step in for Croatia was Igor Matanović, and the striker missed a golden chance when he headed over from close range inside two minutes.
He was punished just 40 seconds later when Duje Ćaleta-Car’s error allowed Milutin Osmajić to race clear and finish under Dominik Livaković.
It was just the third goal Croatia have conceded in this qualifying campaign – and the first on their travels – but within 14 minutes they trailed 2-0.
Nikola Krstović had scored each of his past five goals for club or country before HT, and the Montenegro forward was similarly quick off the mark here, swivelling 20 yards out and firing a low drive past Livaković.
The comeback began eight minutes before the break, though.
Slobodan Rubežić’s sliding challenge on Kristijan Jakić was deemed too forceful by VAR, allowing captain Ivan Perišić to send the spot-kick down the middle on his 150th cap.
Croatia continued to dominate possession in the second half, but Montenegro remained a threat on the break, with Krstović striking the outside of the post from the edge of the penalty area.
The visitors kept pushing, though, and equalised with 17 minutes remaining when substitute Petar Musa’s shot came back off the post, and Jakić was well placed to tuck home the rebound.
Dalić sent Luka Modrić on for his 194th cap as Croatia hunted a winner, eventually finding it with three minutes left, as Vlašić lashed home from 20 yards for his second goal in as many games.
They can now look forward to next summer’s tournament, while Montenegro manager Mirko Vučinić will rue a missed opportunity to end their campaign on a high.
Flashscore Man of the Match: Nikola Krstović (Montenegro)
