The midfielder was in the right place at the right time to convert Ezequiel Lavezzi's cross, having started the flowing move which broke down the Cafeteros and earned three points
Lucas Biglia's goal gave Gerardo Martino a lifeline in the Argentina hotseat, as the nation downed Colombia 1-0 to put their World Cup qualifying campaign back on track.
A miserly two points in the opening three games had sent the Albiceleste near the bottom of the Conmebol standings, and raised questions about the ex-Barcelona man's future on the bench.
But Biglia struck after a fine team move which he started in his own half, giving Argentina some breathing space in the last qualifier of 2015.
Jose Pekerman's team pushed for an equaliser and were denied a penalty when Teofilo Gutierrez went down under a challenge from Ramiro Funes Mori.
Chances were few and far between in the second half, with Argentina limiting their opponents to efforts from outside the box.
Martino's side saw the game out to end Colombia's run of seven home matches in World Cup qualifying without defeat.
The two sides, both having dropped points in their previous fixtures, were positive from the outset as they sought to make amends.
Ever Banega looked impressive in possession but it was Angel di Maria who created the first opening with 12 minutes played, Gonzalo Higuain firing his cutback over the top.
The deadlock was broken eight minutes later as Zapata failed to deal with Ezequiel Lavezzi's cross following a swift Argentina counter-attack, leaving Biglia the simple task of tapping into gaping net.
Zapata could have been dismissed for a trip on Di Maria when the winger raced in behind the Colombia defence, but the referee deemed the foul only to be worthy of a yellow card.
A mix-up between Funes Mori and Sergio Romero almost gifted Pekerman's side a route back into the game in the 34th minute, but the Argentina goalkeeper recovered in time to stop Carlos Bacca converting.
The home fans were calling for a penalty moments later when the Everton defender sent Gutierrez to ground inside the box moments later, though the referee did not agree.
Di Maria could have doubled Argentina's lead five minutes before the interval but, after being released by Higuain, he rolled the ball wide.
Banega fired straight at David Ospina before Frank Fabra fired wide in the 50th minute as the second half began in entertaining fashion.
The tempo of the game suffered as the pitch cut up, with Luis Muriel - on for the second half in place of Macnelly Torres - lashing his first strike at goal high of the target.
Edwin Cardona warmed Romero's gloves with a 25-yard strike but Colombia were unable to find an equaliser.
Paulo Dybala was denied a first international goal by a tight offside call with nine minutes remaining.
In the final minute of normal time, Gino Peruzzi fed Dybala in the box and the Juventus striker did superbly to turn away from Zapata before hitting the upright.
An error from Romero almost resulted in a 93rd-minute equaliser, but Jeison Murillo blasted his shot wide of the target with the keeper out of his net, the lone Biglia strike proving enough for the away team.
The beaten World Cup finalists are next in action away to Copa America nemesis Chile on March 23. Colombia travel to face Bolivia on the same day.
