Royal Troon continued to be a happy hunting ground for Americans as Patrick Reed set the clubhouse target on day one of The 145th Open Championship.
Players from the United States have won the last six Open Championships held at the Ayrshire venue and they dominated the upper echelons of the leaderboard on Thursday with Billy Horschel, Steve Stricker and Justin Thomas all sitting a shot behind Reed.
The 25 year old's 66 equalled the record for the lowest opening round in an Open Championship at Troon on a day of perfect scoring conditions in Scotland.
Reed is without a European Tour win since the 2014 WGC - Cadillac Championship but lost a play-off to Kristoffer Broberg at the BMW Masters last year and gave a strong showing at last week's Aberdeen Asset Management Scottish Open.
The opening holes were providing the best of the scoring and Reed was one of a host of players to take advantage, holing his approach to the par four third before making further gains on the fourth, sixth and seventh.
A bogey on the tenth halted his momentum but he picked the shot back up on the 12th. Another bogey followed on the 13th but a brilliant approach to the last set up a closing gain.
Thomas began his round with four straight birdies and another gain on the seventh saw him reach the turn in 31. A double-bogey on the 15th saw him slip back but the 23 year old got back to four under with a closing birdie.
Stiricker is playing The Open for the first time since 2012 and he last played an Open at Troon in 1997 but he looked very much at home as a strong finish sent him up the leaderboard. The 49 year old was one under after 13 holes but birdied the 14th, 16th and 18th.
Horschel recovered from a bogey on the third with birdies on the fifth, sixth, eighth, 13th and 17th.
Justin Rose is searching for a second Major Championship and he was three under after a 68. The Englishman turned in 35 and then picked up birdies on the 15th and 16th to move up the leaderboard.
Soomin Lee was also two off the lead with a single blemish on the 16th, alongside Richard Sterne and Shugo Imahira.
World Number Four Rory McIlroy was then at two under after a 69 that may prove a good omen as he has gone on to win the last two Major Championships he started with a round in the 60s.
Jamie Donaldson, Vijay Singh, Rickie Fowler, Gary Woodland, Kodai Ichihara and Matt Jones were all also at two under.
Louis Oosthuizen signed for a level par 71, the highlight of which was a hole in one on the short 14th.
