Yoan Gouffran's 42nd-minute goal settled Bordeaux's Ligue 1 contest with Lyon.
The 25-year-old's close-range header extended the home side's unbeaten run to five games, while Lyon - who were clearly second best - have won just one of their last five matches.
Lyon's Bafetimbi Gomis had the game's first chance in the 10th minute when he received the ball from Kim Kallstrom about 25 yards out and shot goalwards - but Cedric Carrasso was equal to the effort.
Bordeaux threatened in the 28th minute when Ludovic Obraniak whipped a free-kick towards the near post but Michael Ciani's glancing header went narrowly wide.
The home side made the decisive breakthrough three minutes before the interval when Gouffran headed in at the far post after Obraniak's free-kick had been touched into his path by Lyon defender Bakari Kone.
Les Girondins started the second half brightly and Poland international midfielder Obraniak came close to doubling the lead in the 56th minute, firing narrowly over after Benoit Tremoulinas had attacked down the left.
The visitors appealed for a penalty three minutes later when Jimmy Briand went down under a challenge from Ciani - but nothing was given.
Lyon goalkeeper Hugo Lloris produced an excellent diving save 17 minutes from time to keep out Jaroslav Plasil's long-range effort.
However, the home side did not pay for failing to double the lead. They controlled the game in the closing stages, with Lyon failing to create any chances of note.
