Rory McIlroy refused to let a last-hole bogey ruin some "ideal preparation" for the British Open as Masters champion Danny Willett suffered more frustration ahead of the season's third Major.

McIlroy carded a superb 66 in testing conditions at Le Golf National to claim a share of the halfway lead in the French Open as Willett’s last competitive appearance before Troon ended in a second consecutive missed cut.

Six birdies in the first 14 holes had taken McIlroy into the outright lead in his first event since missing the cut in the US Open, only for the 27-year-old to drive into the water on the 18th for the second day running.

The resulting bogey left the world number four in a five-way tie for the lead on five under par alongside Mikko Ilonen, Brandon Stone, Thongchai Jaidee and Wang Jeunghun, who won back-to-back titles in Morocco and Mauritius earlier this year.

“It’s a really good day’s work,” said McIlroy, who revealed after his opening 71 that he had whittled 17 swing thoughts “down to about five” as he worked on eradicating some bad habits from his game.

“I can’t let a bit of a disappointing finish taint a really good day. I felt for the most part I controlled my ball well and holed some good putts. Even the ones that didn’t go in looked like they were going to and I’m in a great position going into the weekend.

“It’s a work in progress and it doesn’t feel very natural at the minute, it’s quite mechanical and I am concentrating a lot but if I set up well it tends to go where I want it to.”

McIlroy, who was unable to defend his British Open title in 2015 after suffering an ankle injury while playing football with friends, added: “It’s ideal preparation for the Open, especially with the little breeze we have had as well.

“It’s great preparation to have my last two competitive rounds before the Open in contention in tricky conditions. I can’t really ask for much more than that.”

In contrast, Willett had earlier only been able to add a second round of 72 to his opening 75 to finish five over par and continue a disappointing run of form.

The world number nine finished third in the BMW PGA Championship at the end of May, but smashed the putter he used at Augusta in frustration during the US Open and missed the cut in the BMW International Open in Germany last week.

“The last three weeks we’ve putted as bad as we ever have and things haven’t quite gone our way,” said the 28-year-old from Sheffield. “When you keep shooting the worst score you can it’s a tricky game.

“Just not done anything very well really. Missed a lot of putts, couple of bad shots that cost us and just one of those days again. S*** couple of weeks. It’s fine margins and unfortunately we were on the wrong side of them.”

The last time Willett missed two cuts in a row was coincidentally in the US Open and French Open last year, but he then bounced back to finish sixth in the Open at St Andrews a fortnight later.

Defending champion Bernd Wiesberger had held a four-shot lead when he reached nine under par thanks to five birdies in his first eight holes, but then ran up a triple bogey on the treacherous 18th and also dropped shots on his last two holes.

That left the Austrian a shot off the pace alongside Nicolas Colsaerts and Anders Hansen, the 45-year-old Dane who announced his retirement at the end of last season.

“I just came out to play four events,” Hansen explained after a flawless 68. “I need to play five to keep my status (as a European Tour member) and this week counts for two, so that’s perfect.

“I never expected this and when I came down 15 and saw my name on the leaderboard I was laughing a bit. I thought ‘This is just stupid’. Maybe I’m just more relaxed about the whole thing because it doesn’t really matter.”

Pádraig Harrington made the weekend cut after carding a one-under 70 to finish on one over.

Former double champion Graeme McDowell was always going to struggle after an opening 80 and a two-over 73 left him back on 11 over.

Ryder Cup captain Darren Clarke (80) and Michael Hoey (77) finished on 12 over , with Paul Dunne a show further back after a 78.