Phil Mickelson had a simple message Monday for his Presidents Cup Captain. “Dude, you’ve got to pick this guy,” Mickelson texted to Fred Couples in support of Jordan Spieth’s candidacy.

Mickelson had plenty of reasons to be impressed. Spieth had just shot 62 in the final round of the Deutsche Bank Championship while playing alongside Mickelson. Spieth played the final four holes in 5 under, including an eagle on No. 18, to finish fourth at the final event before the Presidents Cup lineups would be determined.

Couples listened to Mickelson, who has played in every Presidents Cup, and made Spieth one of his two Captain’s selections that were announced Wednesday. Spieth, 20, will be the youngest player to represent the United States in the Presidents Cup. He’s also the first PGA Tourt rookie to participate in the Presidents Cup.

“I’m just super stoked and happy I woke up this morning and it wasn’t a dream,” Spieth said.

Couples also selected Webb Simpson, who finished 11th in the United States’ point standings. The top 10 after the Deutsche Bank Championship automatically qualified for the team.

International Team captain Nick Price used his captain’s picks on Marc Leishman and Brendon de Jonge. The Presidents Cup will be held Oct. 1-6 at Muirfield Village Golf Club in Dublin, Ohio.

Spieth, who turned pro in December, won this year’s John Deere Classic and has eight top-10s this season, second-most on Tour. Spieth is 10th in the FedExCup, while Simpson, the 2012 U.S. Open champion, is 20th. Spieth will be the second-youngest player in Presidents Cup history after Ryo Ishikawa, who was 18 when he played in the 2009 Presidents Cup.

“It’s Jordan Spieth’s time,” Couples said.

Simpson, 28, is the only of the four captain’s picks with previous Presidents Cup experience. He went 3-2-0 in the United States’ victory in 2011 at Royal Melbourne Golf Club in Australia. He finished 11th on the United States’ points standings.

“I just want to say thanks to Freddie and Davis (Love III) and Jay (Haas) and the American team for believing in me,” Simpson said. “I’m so excited.”

Simpson was bumped from the top 10 in the United States’ Presidents Cup standings when Zach Johnson made a 26-foot birdie putt on the Deutsche Bank’s final hole.

“All along, I was going to take No. 11,” Couples said. “And with Webb being in the top 10 for two years only to get pushed out with one putt – there was no way I could leave him off. Webb is a world-class player and a great teammate.

“As for Jordan, I feel like he is one of our top players, even though he is only 20. I’m excited to have a young kid on the Team. I left Keegan out two years ago, and that was a killer decision, and he has become one of the best young players in the game. It’s a team game, and everybody I talked to on the team wanted Spieth. He definitely deserves it.”

This is only the second time in history  – outside of the inaugural event – that three of the four captains’ picks were event “rookies” (2003 – K.J. Choi, Tim Clark, Fred Funk). Two veterans — the United States’ Jim Furyk and the International team’s Tim Clark — were among the notable players who will not participate in this year’s Presidents Cup. Furyk had played on every Presidents and Ryder cup team since 1997.

Clark, a three-time Presidents Cup participant, arrived at the Deutsche Bank Championship at No. 11 in the International Team standings, but missed the cut to drop to 13th.

“Yesterday was one probably one of the toughest days of my life,” Price said. “I had it down to three guys – Marc, Brendon and Tim Clark.  To try and separate the three of them and only pick two was an exceptionally difficult task. You had experience on one hand with Tim, and then you had youth in the two rookies in Marc and Brendon. When push came to shove, it came down to who I felt is going to play Muirfield the best. This is one of those times when you wish there were 13 members of the team.”

The International Team will have seven first-time players, the most in Presidents Cup history, after Price picked two rookies. De Jonge, 33, is No. 26 in the FedExCup after finishing 19th and ninth in the first two Playoffs events, The Barclays and Deutsche Bank Championship. Price also said de Jonge’s left-to-right ball flight is well-suited for Muirfield Village. De Jonge and Price are both from Zimbabwe.

“This was obviously the primary goal starting out last year was to make thsi team, and especially playing for Nick,” de Jonge said. “Nick has been everything to us growing up in junior golf in Zimbabwe., and now to have an opportunity to play for him is definitely a dream come true.”

Leishman, 29, has top-12 finishes at this year’s Masters (T-4), PLAYERS Championship (T-8) and PGA Championship (T-12). Those finishes prompted Price to call Leishman “a guy who is on the rise.” He also finished 16th at the Deutsche Bank Championship. Leishman was in attendance at Royal Melbourne in 1998, when the International Team won for the only time in Presidents Cup history. The Presidents Cup began in 1994.

“I’ve played in some big events this year and feel like I played pretty well around (Muirfield Village), so I feel like I’m a seasoned match player,” Leishman said. “I haven’t played it for a few years, but played it quite a bit at home in Australia as an amateur growing up, so hopefully I can use my experience in that.”

Spieth will be the first player since Tiger Woods in 1996 to qualify for the TOUR Championship by Coca-Cola after starting the season without status; Spieth is the first player to accomplish that feat in the FedExCup era. He also will be the youngest player ever to qualify for the TOUR Championship.

Spieth was low amateur (T-21) in Simpson’s victory at the 2012 U.S. Open. The Walker Cup, a team, match-play competition between amateurs from the United States and Great Britain and Ireland, is being played this week in New York. Spieth was on U.S. team when the Walker Cup was last played, in 2011. He went  2-0-1 and was the United States’ leading points winner in its loss to Great Britain and Ireland in Scotland.

“It’s fun playing one-on-one,” Spieth said about match play. “There’s just a lot more thinking that goes into it, preparing for each shot.”

The U.S. Team has 28 previous Presidents Cup appearances, including three players who have won the Memorial Tournament presented by Nationwide Insurance, played at Muirfield Village Golf Club (Matt Kuchar, 2013, Steve Stricker, 2011 and Tiger Woods, 2012, 2009, 2001, 2000, 1999). The International Team has 17 previous Presidents Cup appearances and one former Memorial champion (Ernie Els, 2004).

The top-10 U.S. players who earned the most official PGA Tour money from the 2011 TOUR Championship by Coca-Cola through the 2013 Deutsche Bank Championship (with money earned in 2013 counting as double) automatically made the U.S. Team.  The top-10 international players (excluding those eligible for the European Ryder Cup Team) from the Official World Golf Ranking after the conclusion of the Deutsche Bank Championship automatically made the International Team.