Clermont escape Grenoble humiliation
The victory gave Clermont a nine-point lead at the top but until Fernandez hit the winning penalty 10 minutes from time, they were staring at defeat against a side who has the league's worst defensive record.
Prop Alexandre Dardet had scored Grenoble's second try of the game which was converted by Jonathan Wisniewski for a 20-18 lead. But Fernandez kept his nerve with his first kick of the game after replacing Camille Lopez.
Earlier, Morgan Parra and Otar Giorgadze had crossed for Clermont for a 15-7 half-time lead, with South African wing Gio Aplon keeping second-from-bottom Grenoble in touch.
Clermont, unbeaten at home all season, still had to ride out a nervy ending to the game when Wisniewski missed a drop goal which could have secured a shock victory.
"We are happy to take four points tonight. We played a great team in Grenoble but we already knew this before kick off," said Clermont coach Franck Azema.
Defending champions Racing 92 scored two tries in the last eight minutes to beat fellow title hopefuls Montpellier 21-9 in a drab affair in Paris.
Playing without injured All Blacks legend Dan Carter, Racing were locked at 9-9 until the 72nd minute with Johannes Goosen and Ben Botica exchanging three penalties apiece. But Henri Chavancy blasted through three tackles to score, with fellow academy graduate Xavier Chauveau adding a second try three minutes from time.
Toulouse also left it late to secure a 16-15 win over Castres at their Stade Ernest-Wallon home. Missing six of their first-choice squad who are away on international duty with France, Toulouse needed a penalty two minutes from time by Samuel Marquesto steal the win.
Rory Kockott kicked five penalties for Castres but his miss from just 22 metres in front of the posts with five minutes left proved costly.
Bordeaux ran in four tries in an impressive 37-19 win over Stade Francais. Most of the damage was done in the first half when they stretched to a 27-7 lead with tries from New Zealand No.8 Hugh Chalmers, hooker and captain Clement Maynadier and centre Julien Rey.
Scrumhalf Yann Lesgourgues added a second half try while Kiwi flyhalf Simon Hickey kicked a personal haul of 17 points.
French Top 14 results:
Bordeaux 37-19 Stade Francais
Toulouse 16-15 Castres
Brive 26-9 Bayonne
Clermont 21-20 Grenoble
Racing92 21-9 Montpellier
Sunday's fixtures:
La Rochelle v Pau
Lyon v Toulon
French Top 14 table:
(played, won, drawn, lost, points for, points against, bonus points, total points)
Clermont 10 7 2 1 313 211 4 36
Toulon 9 5 1 3 238 183 5 27
Montpellier 10 6 0 4 225 175 3 27
Toulouse 10 6 0 4 210 199 3 27
Bordeaux-Bègles 10 6 0 4 256 238 2 26
Racing92 10 6 0 4 222 212 2 26
La Rochelle 9 4 2 3 237 191 5 25
Brive 10 5 1 4 225 254 1 23
Castres 10 4 1 5 246 210 3 21
Stade Français 10 4 1 5 254 260 2 20
Pau 9 3 0 6 199 225 5 17
Lyon 9 3 2 4 184 221 1 17
Grenoble 10 2 0 8 214 326 4 12
Bayonne 10 1 2 7 145 263 0 8
Agence France-Presse