Popovich takes the reins beginning with the team's 2017 training camp. He will coach the team at the 2019 World Cup and 2020 Olympics, should it qualify.
"Knowing that there was going to be an end to Coach K's tenure, the question of course internally and then externally was who was going to be next?" Colangelo said. "All roads led to Pop. It's as simple as that. Why is that? It's because of who he is, his character, his leadership. He's a winner. He's a leader, sacrificing attitude in terms of being a military guy. He's respected by everyone in the basketball world, and his legacy of course relative to his championships is extraordinary."
Colangelo said the timing was perfect to move Popovich into his new role before the coach had to start the NBA regular season "to make it a very seamless transition."
Considered one of the top coaches in the NBA and internationally, Popovich will take over for Krzyzewski, who led the Americans to consecutive Olympic gold medals, a pair of world titles and a 75-1 record. Krzyzewski will stay aboard as an adviser to Colangelo, who will remain in his role. Popovich said he wouldn't have taken over unless Colangelo remained.
Popovich, who tried out for the 1972 Olympic team, said, "Any one of us who is involved in any sport, whether you're a player or a coach, would love to be involved with the Olympic program."
"So to say that way back then when I was in my early 20s and we all had a dream to make an Olympic team ... that never leaves you," he said. "You grow up and you watch the Olympic Games on TV and you always want to be a part of something like that. I'm no different than anybody else. So in that sense, it does have an added meaning. [I] never thought about being in this position at that point in your life. To be here now, it's quite astonishing."
Popovich served as an assistant on the U.S. team during the 2002 world championships and 2004 Olympics. LeBron James, who has played in three Olympics, told The Associated Press that "Team USA is in good hands" with Popovich.
"It was in good hands with Coach K. It's almost like 'The Godfather,'" James said. "We hand it off to Michael Corleone now."
When Krzyzewski decided to step down next summer as coach of the U.S. team, Colangelo wanted to name a successor as soon as possible.
"Everything in life is about timing," Colangelo said. "I think it was meant to be right now. After we spoke, I gave him plenty of time to think about it. The question is, did I have a Plan B? No, because I really expected and I anticipated that he would eventually say, 'I want to do this.' And he did.
"I had a short list, and it started and ended with Pop. When we met, we had a great session. We talked about a lot of things: the past, the future. The more important thing is, where are we going, going forward? He asked me a question. He said, 'What about you? Are you going to stay on? Are you going to continue? Because if you're not, then I don't have interest.'"
Popovich, 66, owns a 1,022-470 record with the Spurs. During the offseason, there was speculation about how long Popovich would remain their coach. When courting LaMarcus Aldridge in free agency, Popovich assured the former Trail Blazer that he would remain coach of the Spurs for the duration of the player's new four-year contract.
The new responsibility with the U.S. team could keep Popovich in the fold even longer in San Antonio.
"In all of our lives, if you can keep challenges in front of you, I think it's a good thing," Popovich said. "I'm not ready to plant tomatoes day in and day out or do anything like that. I think if you can look ahead to challenges you're gonna have, you stay young. You stay excited. You stay vibrant. So this is exciting, very exciting for me. And I think it makes me sharper for the Spurs."
The U.S. team took third in its first tournament, the world championships, under Krzyzewski in 2006, and has captured victories in 63 consecutive contests, including gold-medal finishes at the 2008 Beijing Olympics, 2012 London Olympics, and 2010 and 2014 FIBA World Cups. The U.S. team will be favored to capture a title next summer in Rio de Janeiro.
But a new qualification system for future worlds and Olympics will be utilized by FIBA, basketball's governing body, after next summer, and will include games during the NBA season that Popovich will be forced to miss. The NBA doesn't plan to stop the schedule for FIBA competitions, which would make NBA players and Popovich unavailable for international games.
Colangelo said the situation "changes how we do business for USA Basketball. There are so many windows of qualifying times during the course of the year that will take place in '17 and '18. We're focused on the national team for now, which is '19 and '20. We have a lot of plans and thoughts, nothing etched in concrete regarding what we're going to do in '17 and '18. We may see a lot of D-League players because of the times during the year that we have to participate, and we'll do all that we have to do. But the continuity that we've developed with our senior men's team in bringing along the select players, and the young players, we're gonna continue with that because one of our first jobs is to look at who is going to be out there in '19 and '20. Well, you get ready in '17 and '18, and that's the plan."
NBA commissioner Adam Silver complimented USA Basketball on its choice of Popovich.
"For the USAB program, I think it's fantastic you've gone from Coach K, who will go down as the greatest or certainly one of the greatest college coaches of all time, to an NBA coach viewed as one of our greatest coaches ever," he said.
Popovich was widely considered the best coach to take over for Krzyzewski, considering his championship pedigree, having won titles in 1999, 2003, 2005, 2007 and 2014 and the NBA coach of the year award on three occasions. Popovich is the longest-tenured active head coach in professional sports and doesn't expect his new duties to take away focus from the Spurs.
"It's got to be more than work. It's got to be enjoyable. It's got to be something you get a kick out of, that inspires you, that challenges you," Popovich said. "All those things are what we all look for as human beings. It makes life worthwhile. So it's got nothing to do with being tired. There are all kinds of time during the day to get things done."
Information from The Associated Press was used in this report.
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Spurs coach Gregg Popovich reacts to being named the new USA basketball head coach starting in 2017.
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