Lens secured their second Ligue 1 win of the season tonight - and condemned Grenoble to their third straight defeat.
Abdoulrazak Boukari netted the second-half winner for the visitors after Eduardo dos Santos' early opener had been cancelled out by Daniel Ljuboja.
The hosts remain languishing at the wrong end having failed to pick up a point so far, while Les Sang et Or climbed to sixth.
Dos Santos opened the scoring this afternoon with a fine individual effort in the sixth minute, picking the ball up in midfield and accelerating towards goal before unleashing a left-footed finish past Jody Viviani.
The home team restored parity five minutes later, however. A Laurent Batlles corner from the right was cleared by the Lens defence, but Ljuboja met the rebound with an acrobatic volley from inside the area to give Vedran Runje no chance.
Grenoble had a couple of opportunities to go ahead in the first half, but Runje denied first Batlles with a fine low save and then Ljuboja from a fierce left-footed free-kick.
With all to play for after the interval, Lens goalkeeper Runje had to remain alert to keep out an effort from Ljuboja after good link-up play with Batlles just after the hour mark.
Midway through the second half the decisive goal did arrive and it went to the visitors.
Dejan Milovanovic fired a free-kick into the area and Boukari rose above the Grenoble defence, beating Viviani to the ball and heading home.
Grenoble continued to push forward looking for the elusive equaliser which would have secured their first point of the campaign, but it was not forthcoming.
Ljuboja smashed in a half-volley from the edge of the area but Runje gathered, and Batlles screwed a left-footed attempt wide as Mecha Bazdarevic's side tasted defeat for the third successive match.