In the midst of drastic changes to his swing, Rory McIlroy shot a level-par 71 at the French Open to lie five shots off the lead held by Lucas Bjerregaard midway through the first round on Thursday.

McIlroy, currently in the spotlight because of his decision to skip the Olympics over concerns about the Zika virus, had four birdies and four bogeys around L'Albatros course at the Le Golf National, the 2018 Ryder Cup host.

The fourth-ranked McIlroy said, "I've got about four or five swing thoughts out there at the minute, so that's why I'm sort of happy with 71."

Bjerregaard shot a 5-under 66, helped by a hole-in-one at No. 2 from 202 yards. The Dane was playing with a new set of clubs after his own was lost in transit.