Xherdan Shaqiri scored a late winner to help Switzerland stun Serbia 2-1 in their second Group E game on Friday.
The result puts the Swiss, who are guaranteed to advance with a win in their final game, level on points (four) with first-place Brazil in the group, while Serbia slump to third after winning their opening match against Costa Rica.
Serbia went in front in the fifth minute when Aleksandar Mitrovic, after missing a header moments earlier, rose above a Swiss defender and wonderfully guided a Dusan Tadic cross from the right past goalkeeper Yann Sommer and into the far corner.
Switzerland worked their best chance of the half on 30 minutes -- Blerim Dzemaili darting onto Steven Zuber's cross but wasn't able to make enough contact to beat Vladimir Stojkovic with a leaping toe poke while under pressure.
Serbia nearly had their second just before the half but Dusko Tosic's diving header from point-blank range skidded off his head to Nemanja Matic who couldn't react fast enough to finish the chance.
Switzerland wasted little time in finding their equaliser after the break with Granit Xhaka pouncing on a blocked Shaqiri shot and firing an unstoppable blast from outside the box past a helpless Stojkovic on 52 minutes.
The goal made Xhaka the third-ever Swiss player to score in multiple World Cups, joining Andre Abegglen (1934, 1938) and Jackie Fatton (1950, 1954) on the historic list.
Shaqiri shaved the outside of the post six minutes later with a curled snapshot from the edge of the box that left Stojkovic well beaten.
Mitrovic could not reach an inviting cross across the goalmouth in 69th minute, the Newcastle man arriving just late on the far post as the ball rolled out of play.
Substitute Breel Embolo stung the hands of Stojkovic with a powerful effort from distance in the 82nd minute as Switzerland turned up the pressure late.
And Shaqiri would secure the points on the stroke of 90 minutes when he broke behind the defence and rolled his shot past a charging Stojkovic to make Switzerland the first team to score a come-from-behind victory in Russia.
With their group destiny in their hands, Switzerland will wrap up group play against already-eliminated Costa Rica in Nizhny Novgorod on Wednesday, while Serbia will face Brazil in Moscow that same day.