It has been a long walk on a seemingly perpetual uphill fairway for former Milton High and Georgia Tech player Roberto Castro. Leaving Tech in 2007 with his degree in industrial engineering, Castro was relegated to the second-tier tours for three years before earning his spot on the PGA Tour last season.

And now look at him, here at East Lake, a 15-minute commute from his home, playing with the elites at the Tour Championship. And not just showing up, either. Castro shot a 3-under 67 on Thursday to put himself only three shots off the lead of Henrik Stenson.

You know you made it when … “your caddie is staying at The Ritz-Carlton,” Castro joked.

Castro himself is staying at home, a treat after a long season on the road. But a profitable one. He has ground out one runner-up finish (at the AT&T National) and 10 top-10 finishes to pocket nearly $2 million and earn a spot at the Tour Championship.

“I’ve made a few more putts. I’m a little more comfortable on the greens. And I’ve gained a little more experience every week,” he said.

Of the 100 or so rounds Castro figures he has played at East Lake over his life, Thursday’s might have been the most enjoyable.

“I had a bunch of friends come out,” he said. “It was great to see some familiar faces at the first tee. Usually when I’m playing with somebody, I’m hearing ‘War Eagle!’ or something other than ‘Go Yellow Jackets.’ It was nice to get a few shout-outs today.”

Phil's putting ills: No pretty way to say it, Phil Mickelson seemed lost on the greens Thursday.

He took 34 putts in the first round, last in the field, tied with Tiger Woods. Mickelson was lipping out all over East Lake. He missed a 3-footer for birdie on No. 2, a 5-foot par putt on No. 4 and putts inside 4 feet for par on No. 5 and a birdie on No. 15.

His 71 was his worst Tour Championship first round since 2009.

Serigo uninspired: Sergio Garcia was less than swept away by the atmosphere at East Lake on Thursday.

His first comments to the media afterward concerned a perceived lack of excitement on the other side of the ropes.

Sounding more like someone who shot 78 rather than 68, Garcia said afterward, “I’d love to feel a little bit different out there on the course. You know, I’d love to feel a little bit more energy, probably what this tournament deserves.

“But unfortunately I had to play where I had to play, and it’s kind of dragging on a little bit.”

His twosome was occasionally, “Boooooed,” but it had nothing to do with Garcia’s past intemperate comments about Tiger Woods. He was paired with Boo Weekley.”

Revenge of the rookies: You can almost hear Larry Munson now, growling, "My, God, a freshman!" Oh, wait. That's Horschel, not Herschel near the top of the leaderboard. Billy Horschel, at 3 under, was one of the eight players making their first appearance in the Tour Championship. Many are making sizable splashes.

Apparently that whole “there is no substitute for experience” thing is overrated. There is a first-timer, Henrik Stenson, at the top of the leaderboard. Combined, the eight rookies shot 19 under Thursday. Only one, D.A. Points (72), was over par.

“It’s a fun, fun event,” Horschel has discovered. “My game’s in a good spot. I may have not played the way I would have liked the last couple of months, but I’ve been seeing some good signs the last few weeks.”