Defending champion Jordan Spieth assumed his customary position on a crowded leaderboard in the early stages of the 80th Masters on Thursday.

Spieth, who was second on his debut in 2014 and claimed a first green jacket with a record-breaking performance 12 months ago, is looking to join Jack Nicklaus, Nick Faldo and Tiger Woods in making a successful title defence at Augusta National.

And the world number two, who led from start to finish after an opening 64 last year, was quickly into his stride with birdies on the third and sixth taking the 22-year-old into a share of the lead with playing partner Paul Casey and Open champion Zach Johnson.

Nine players were just a shot behind on one under, including US Amateur champion Bryson DeChambeau and Ryder Cup trio Justin Rose, Lee Westwood and Jamie Donaldson.

Conditions were good for the early starters after heavy overnight rain, but the wind had started to pick up and was forecast to strengthen during the day with gusts between 30 and 35mph predicted.

That was bad news for world number three Rory McIlroy in his bid to win a first green jacket to complete the career grand slam, the 26-year-old being the last man out shortly after 2pm local time.

The first man out, American Jim Herman, had made a dream start to his debut after securing the last place in the 89-man field by virtue of winning the Shell Houston Open.

However, the former assistant professional at one of the courses owned by US presidential candidate Donald Trump, then carded a hat-trick of bogeys from the fourth and had dropped back to two over par with four holes to play.

World number five Rickie Fowler ran up a double-bogey on the first after hitting a tree with his second shot, but bounced back with birdies on the second, third and fifth before dropping back to level par with a bogey on the seventh.

Spieth, who set records for the highest number of birdies (28) and lowest 36 and 54-hole totals in Masters history last year, moved into the outright lead after pitching to three feet for birdie on the par-five eighth.

And although Casey, who was sixth here last year and on his debut in 2004, briefly got back on level terms with a birdie from 25 feet on the 10th, Spieth simply followed the Englishman in from half the distance to move back in front on four under.

The American trio of Dustin Johnson, Keegan Bradley and Daniel Berger were two off the lead, with the 21-year-old Matt Fitzpatrick another stroke back after following birdies on the first two holes with a bogey on the third.