PARIS, FRANCE - JULY 04: Kevin Stadler of USA making a birdie putt on the 15th green to go 11 under for the tournament during the Alstom Open de France - Day Two at Le Golf National on July 4, 2014 in Paris, France. (Photo by Tony Marshall/Getty Images)

Versailles - American Kevin Stadler was the early clubhouse leader at the French Open on Friday as a second-round, three-under-par 68 extended his advantage to three shots at Le Golf National.

Many of the field were yet to tee off as rain and adverse conditions played into the hands of Stadler who was one of the early starters and took full advantage to stand 10-under-par after 36 holes.

Another solid round that featured four front-nine birdies and two more down the stretch was only marred by a double bogey at the 18th which denied the 34-year-old an even bigger lead.

“I tried to get a little too much out of my third shot on 18 and didn't have a great lie so it's not a great way to finish the day but overall it's another good day, so all good,” said Stadler.

“I definitley didn't expect to be 10 under after two days but I played well in the Pro-Am and I'm very pleased with 10 under. It's a ball strikers' golf course and really set up well with great greens.

“I played really well for 16 holes and then a couple sloppy ones but it's a challenging course and even if I played 36 good holes, the last one is what it is,” added Stadler in reference to his double bogey finish.

Stadler, who won his second professional title in February when he lifted the Phoenix Open crown, has so far been better known as the son of 13-time PGA winner Craig 'the Walrus' Stadler who won the 1982 Masters in a playoff.

In April, they became the first father-son duo to play at the Masters where Kevin finished in a tie for eighth on his debut at Augusta.

“Overall it's a very good day, I don't know if the lead will hold up, there's still half a day to go and the weather's supposed to get nasty the next couple days so we'll have to wait and see,” continued Stadler.

Victor Riu gave home fans real hope of a first French champion since Thomas Levet in 2011 with a 67 to lie second, three shots behind Stadler on seven under.

The only victory to date, for the 29-year-old from Saint-Nom-la-Breteche, was on the Challenge Tour in 2013 when he won the Swiss Challenge by three shots.

Germany's Marcel Siem, the 2012 French Open champion, remained in third spot but now four strokes off the lead as he was one of the later starters.

Scotland's Stephen Gallacher is a further shot back on five under and also scheduled to tee off in the afternoon.

Defending champion Graeme McDowell of Northern Ireland finished strongly with birdies at the 11th and 16th to finish his second round on three-under-par and seven shots off the lead.

US Open champion Martin Kaymer shot a one-under-par 70 and looks set to make the cut but now needs to make up nine shots on Stadler if he is to win a second French Open after triumphing on the Albatross course in 2009.