Spain's Ricky Rubio will face the U.S. in the semifinals, with assistant coach Tom Thibodeau of the Wolves looking on from the bench. (Brian Stensaas — Associated Press/The Minnesota Star Tribune)

RIO DE JANEIRO - Tom Thibodeau and Ricky Rubio met earlier this summer in Minneapolis and have spoken briefly in Rio. The new Timberwolves coach and his inherited point guard will duel, in their own way, in the semifinals of the Olympic basketball tournament, months after Thibodeau selected another point guard with the fifth pick in the draft.

Both are peaking just in time to make the matchup important for the U.S. as well as fascinating for Timberwolves fans.

Rubio played two sloppy, unproductive games as Spain started the tournament 0-2. In his past four games, he has reprised his NBA career, running Spain's offense, playing intense defense and making himself an asset even when he hasn't shot well.

The United States went through a three-game funk caused in part by inattentive defense before rallying to throttle Argentina in the quarterfinals.

Friday, the savvy point guard will face the defensive wizard who will determine the course of his career, as the two work through the early stages of a portentous relationship.

Thibodeau has studied Rubio as an NBA player, and an Olympian.

''I've watched him quite a bit,'' Thibodeau said Thursday at the U.S. team practice. ''I watched a lot of our games from last year and of course here. And from coaching against him I think I have a pretty good feel for all of the things he brings to a team.

''He has the ability to make other people a lot better. He gets easy baskets for everybody. Very unselfish, plays for the team. We're concerned, but I'm glad that he's healthy. I had a chance to talk to him yesterday for a few minutes, and he seems to be doing well.

''He came in for a few days at the beginning of the summer, back in Minnesota, so we had a chance to visit. Then he'll be coming back early to get started. I look forward to it.''

Rubio revived his game just in time to help Spain qualify for the elimination rounds of the tournament. In his first two games, both losses, he produced three points on 1-for-6 shooting, with one assist, eight fouls and three turnovers, and was minus-6.

In the four games since, Rubio has produced 36 points on 11-for-22 shooting, with 17 assists, eight fouls and five turnovers, and was plus-87.

Friday he'll test his improved play against the world's most talented team.

''It would mean everything for us,'' Rubio told the Associated Press about beating the U.S. ''It would mean the world. I remember watching Argentina beat the U.S. in 2004, and I think maybe the same story that Argentina wrote with the 'Gold Generation,' we can write too.

''We've been battling against them for a long time. We've always come up short. It would be a dream for us to beat them. I really think we can do it, but we have to have the perfect game.''

The tournament may have turned around for Spain when Rubio made a midcourt steal leading to a layup that gave Spain breathing room against Nigeria in the third game. The tournament may have turned around for the U.S. when Kyle Lowry, Paul George and Jimmy Butler played together late in the first quarter of the quarterfinal and suffocated Argentina's offense.

Kyrie Irving dived on the floor, prompting one of many wild celebrations on the American bench. It was as if the U.S. had tired of struggling against less-talented opponents and brought enthusiasm as well as defensive pressure to the game.

''We made several hustle plays in that game,'' Thibodeau said. ''When you make great effort plays they tend to unite and inspire the team.''

The U.S. beat Spain in the gold medal game in the past two Olympics. Friday, Rubio passing will try to shred Thibodeau's defense, as the two Timberwolves get to know each other a little better.