SEVILLE, Spain, May 4, 2012 (AFP) - Bourdy, who boasts only one top-ten finish in his last 24 European Tour events, made four birdies in his last six holes to card a six-under-par 66 which left him at five under par for the tournament.
Having resumed down in 37th place, he now leads England's Simon Dyson and Robert Rock, Italian teenager Matteo Manassero and Spaniard Jorge Campillo, by one shot.
Overnight leader Shaun Micheel managed only a 77 as the 2003 US PGA Champion slipped back to level par.
Despite the tough conditions -- which included wind and dense rough -- Bourdy's 66 was the best round of the week so far.
"I've just been patient," said Bourdy. "I've not made a score like that for a long time in these conditions. It's good for the confidence.
"I'm very happy about this round, particularly in these conditions. I made eight birdies and just two bogeys.
"Yesterday one over was not so bad in that wind, but today (Friday) I played really well, I felt comfortable and very solid, very consistent and I also made some important putts, so I'll try to keep going like this."
Dyson carded a 69, finishing with a 12-footer for eagle.
"It appeared to bobble and I started walking, but it kept going and dropped," said Dyson, the reigning Irish Open champion who is using a new belly putter.
"I switched because I've just not been holing out well. It's harder to get the pace, but I start it on the right line more consistently."
Manassero and Rock shot 70 and 72 respectively as they continued their bids for third European Tour wins.
"It wasn't an easy day and I'm happy because I didn't really play that well but managed to score," said Manassero, 19.
"I'm really happy to be in contention, to be around the lead, and we shall see what happens."
Leading second-round scores from the Spanish Open on Friday (GBR and IRL unless stated, par 72):
139 Gregory Bourdy (FRA) 73 66
140 Robert Rock 68 72, Jorge Campillo (ESP) 68 72, Matteo Manassero (ITA) 70 70, Simon Dyson 71 69
141 Soren Kjeldsen (DEN) 71 70, Francesco Molinari (ITA) 70 71, Danny Willett 68 73, Graeme Storm 70 71
142 Gary Orr 70 72, James Kingston (RSA) 74 68, Matthew Baldwin 69 73, Thongchai Jaidee (THA) 73 69
143 Sam Hutsby 70 73, Marcel Siem (GER) 71 72, Rafael Cabrera Bello (ESP) 70 73, Darren Fichardt (RSA) 75 68, Pablo Larrazabal (ESP) 71 72
144 Richard Bland 73 71, Richie Ramsay 73 71, Shaun Micheel (USA) 67 77, Nicolas Colsaerts (BEL) 72 72, Peter Lawrie 71 73
145 Emiliano Grillo (ARG) 73 72, Chris Wood 72 73, Jack Hiluta 72 73, Anders Hansen (DEN) 72 73, Thorbjorn Olesen (DEN) 73 72, Fabrizio Zanotti (PAR) 72 73, Lee Slattery 74 71
146 Phillip Price 73 73, Kenneth Ferrie 72 74, Raphael Jacquelin (FRA) 76 70, Marc Warren 72 74, Raul Quiros (ESP) 73 73, Alejandro Canizares (ESP) 74 72, Adrian Otaegui (ESP) 73 73, Simon Thornton 73 73, Gregory Havret (FRA) 72 74