The Colombian netted his fourth goal in five games from 12 yards, beating Fabien Audard after being felled by the Lorient goalkeeper.
The Brittany club did have chances to get back into the game, Sadio Diallo seeing an effort ruled out for offside midway through the first half, but the hosts always looked to be in control and now aim to maintain their momentum when they face champions Paris Saint-Germain in a mouth-watering clash at the Parc des Princes on September 22.
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Remi Garde's men headed into the game on the back of disappointing defeats to Reims and Evian but were boosted by the return of striker Bafetimbi Gomis, who came close to joining Newcastle in the transfer window.
However, the France international could not inspire the hosts to victory as Rennes held on to make it just one defeat in five games for Philippe Montanier's side.
Nice won their second game in as many seasons at Lille's Stade Pierre-Mauroy, Claude Puel's men easing to a 2-0 victory. The visitors won by the same scoreline last season and had little difficulty in seeing off the 2010-11 champions once again, Argentinian striker Dario Cvitanich scoring a double.
Cvitanich scored 22 goals for Nice last term and it was his clinical finishing that proved to be the difference this time around. The 29-year-old gave the visitors the lead after 20 minutes, latching on to a neat flick from Christian Bruls to hammer a shot past Victor Enyeama, before combining with the same player just before the break for his second.