Dustin Johnson overshadowed Jordan Spieth on the opening day of the 2015 Open Championship, finishing the round top of the leader board at St Andrews.
Johnson finished second behind Spieth at last month's US Open but has the edge over the young Texan after posting a seven under par 65 on day one.
Scotland's Paul Lawrie, who won the competition in 1999, sits just one off the leader with Zach Johnson and Englishman Danny Willett also among a pack of six tied second at six under.
Spieth, who is attempting to become the first man since 1953 to win the first three majors of the year, carded a 67 and sits two shots off the lead, tied for third alongside South African pair Charl Schwartzel and 2010 champion Louis Oosthuizen.
The 21-year-old bogeyed on the 13th and 17th but remains optimistic ahead of another tussle with Johnson.
I'm very pleased with the start," Spieth said. "I saw a 65 in our group and if DJ keeps driving it the way he is, then I'm going to have to play my best golf to have a chance.
"It's hard to argue with somebody who's splitting bunkers at about 380 yards and just two-putting for birdie on five or six of the holes. I don't have that in the bag, but I've played enough golf with him to where I believe in my skill set that I can still trump that crazy ability that he has."
Tiger Woods' miserable run of form has continued and the 14-time major winner already sits 11 points off the lead after finishing four over with three rounds remaining. Woods, who twice won this competition at St Andrews in 2000 and 2005, scored two bogeys on his first two holes and is already in danger of missing the weekend cut after recording his worst Open score.
Lee Westwood also endured a tumultuous start in his attempts to get his hands on a career first major, bogeying in his last three holes to come crashing down the leader board to finish the day one under.
2013 champion Phil Mickelson was one of the last to tee off on Friday and ended the evening two under along with Justin Rose.
Early on Sweden's David Lingmerth equalled a course record when he hit an outstanding 29 on the front nine but couldn't continue that momentum, carding a 69 to finish the day three under par.