Clermont retained their French Top 14 lead with a gritty 19-8 win at Oyonnax, but a bonus-point 40-17 triumph for champions Toulon over Montpellier trimmed their advantage at the top.
Clermont had struggled to a 6-3 lead at half-time with Brock James kicking two penalties although they should have been out of sight at that stage.
Loosehead prop Thomas Domingo had been held up at the line when he would have been better advised releasing either the fleeter Nick Abendanon or Napolioni Nalaga, both unmarked outside him.
Centre Wesley Fofana then failed to ground the ball after chasing down a cheeky kick ahead from Morgan Parra.
But after James had potted another penalty early in the second half, Clermont got the try their pressing deserved when replacement lock Jamie Cudmore plundered the score.
James hit the conversion before Parra succeeded with a monster penalty to stretch the lead to 19-3.
A try five minutes from time by Tongan flanker Viliami Maasfu was too little, too late as Oyonnax lost their unbeaten home record.
Toulon, who destroyed Brive last week in a eight-try running fest, touched down five times against fellow south coast club Montpellier earlier on Saturday.
Thanks to their bonus point Toulon now have 24 points and are three behind Clermont.
“Overall I’m proud of the spirit my players have shown since the beginning of the season,” said Toulon coach Bernard Laporte.
“The scoreline wasn’t very flattering for us at the break, but we lacked efficiency. The try (Lucas Dupont) just before the break hurt us but we can’t hold it against our rivals for being good.
“After that we created a lot of chances because we’ve worked hard on how to bounce back in training.”
Toulon made up for their defeat against Stade Francais at home two weeks ago, scoring five tries through David Smith (13), James O’Connor (33, 59), Matt Giteau (49) and Delon Armitage (59).
The hosts held a narrow first half lead of 17-14 at the break, with Montpellier keeping in touch through tries from Jonathan Pelissie (22) and Lucas Dupont (40).
But the visitors lost momentum after the break, notching up just three more points.
Castres, the 2013 champions and runners-up to Toulon last season, suffered their fifth defeat in seven league games, losing 28-18 at promoted Lyon.
Castres are second from bottom, propped up only on points difference by La Rochelle.
They had led 11-9 at half-time but their hopes unravelled in the second period with Ricky Januarie, former Castres star Paul Bonnefond and Romain Loursac scoring tries in a decisive 20-minute spell.
Winger Romain Martial had put Castres in front with third-minute try and after Christopher Tuatara had cut the deficit to 28-18 in the 76th minute, Martial had the chance to at least secure a losing bonus point in the dying moments.
But in a snapshot of Castres’ woeful season, he allowed the ball to escape from his grasp after a fine tackle from Mosese Ratuvou.
“We cannot be satisfied. There were too many gaps, we were too indisciplined,” said Castres manager Matthias Rolland.
“But we won’t go forward by burying our heads in the sand.”
Racing Metro were also amongst Saturday’s losers, going down 27-25 at Grenoble for whom South Africn scrum-half Charl McLeod, Irish centre Chris Farrell and Fijian wing Alipate Ratini all scored tries.
Grenoble are up to fourth spot with 20 points while Racing are sixth thanks to Antonie Claassen scoring a last-minute try to snatch a bonus point.
Stade Francais, beaten 23-3 at Montpellier last week, got back to winning ways with a seven-try demolition of La Rochelle in a 43-10 triumph at Stade Jean Bouin.
Centre Jonathan Danty and winger Julien Arias both scored two tries apiece for the Paris giants.
Struggling Toulouse slumped to a fifth successive defeat Friday as Bayonne claimed a 35-19 win in a match which saw the indisciplined 19-time French champions play for an hour with 14 men.
Bayonne outscored Toulouse four tries to one to also claim a winning bonus point as the struggling Top 14 giants paid a heavy price for Corey Flynn’s 20th-minute red card for stamping.
Saracens director of rugby Mark McCall tried to allay concerns over the fitness of Owen Farrell after the England outside-half missed Saturday’s 40-19 Premiership win over Sale with a thigh strain.
Fears had been raised over Farrell’s availability for 2015 World Cup hosts England’s November internationals at home to New Zealand, South Africa, Samoa and Australia after he suffered the injury in last weekend’s 36-32 victory against London Irish.
Farrell also missed the last Test of the June series against world champions New Zealand because of a knee problem and returned to the treatment room having started just one match of the new European season.
However, McCall, speaking after Saracens’ comprehensive defeat of Sale – a result that left last season’s losing Premiership finalists with the only perfect played four won four record in this term’s English top flight – said: “We don’t expect Owen to be out for long, we’re looking at it on a week by week basis.
“It’s a very minor strain and we’re looking at a couple of weeks, maximum.”
Bath, fresh from their spectacular 45-0 thrashing of Leicester last weekend, saw their unbeaten start to the Premiership end with a 31-24 loss away to champions Northampton.
After the match, Northampton boss Jim Mallinder also found himself playing down injury concerns regarding the Saints’ trio of England forwards in Tom Wood, Courtney Lawes and Alex Corbisiero.
Neither flanker Wood nor lock Lawes started the match while injury-plagued prop Corbisiero went off during the second half at Franklin’s Gardens.
“Alex took a bang to his shoulder. I don’t think it is anything worse than that,” Mallinder said.
“Tom has got a bit of a sore back and Courtney a sore shoulder,” he added. “They are improving and hopefully with an extra week they will be fit to play down at London Irish next Saturday.”
Northampton came through a gruelling match, scoring an early penalty try before Calum Clark crossed Bath’s line.
Second-half tries from lock Christian Day and centre George Pisi helped secure the bonus points, with Saints fly-half Stephen Myler landing all four conversions and kicking a penalty too.
Bath pushed Northampton hard, though, thanks to tries by prop David Wilson, wing Olly Woodburn and replacement foward Nick Auterac, with England fly-half George Ford kicking a penalty and three conversions.
Meanwhile Leicester boss Richard Cockerill risked disciplinary action by slamming referee Greg Garner after the injury-hit Tigers, with nearly half their first-choice team sidelined, suffered back-to-back defeats with a 22-19 loss at home to London Irish.
Cockerill was at a loss to understand how Leicester No 8 Jordan Crane was sent to the sin-bin for barging into a ruck while Exiles flanker Blair received nothing more than a talking-to after appearing to punch Jamie Gibson in the face.
“If a punch in the face is a penalty and a ticking off – I thought it was an automatic red card - and a player who drops his shoulder into someone lying on the wrong side gets a yellow card ...
“I didn’t think the referee had a good performance,” Cockerill said. “Clearly, Greg Garner thinks it’s all right to punch someone in the face and it’s a penalty.
“I don’t want any sympathy, I just want referees to referee properly,” the former England hooker added.
“The Jordan Crane decision was pretty off the scale.”
Shane Geraghty kicked a penalty following Crane’s yellow-card that saw London Irish win at Welford Road for the first time in 11 years.
“The result is great, but we are not crowing because we realise the Tigers are wounded,” said London Irish boss Brian Smith, the former Australia and Ireland fly-half.
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