Update [Friday, 9:00 p.m. ET]: The United States claimed an 82-76 victory over Spain to advance to Sunday's gold medal contest against Serbia. Guard Klay Thompson led the U.S. with 22 points. Serbia defeated Australia in the late-game semifinal, 87-61.

Original Story 

Four teams remain in the 2016 Rio Games men’s basketball tournament, but only one will finish the weekend donning a gold medal. The United States, Spain, Australia, and Serbia have all reached the semifinals and are vying for a spot in the championship.

All four gold hopefuls roll out current NBA players and each has shown flashes of a world championship team, making the final stages of the tournament too difficult to call.

As of publishing, the U.S. is currently facing Spain and Australia will battle Serbia in today. The winners move on to the gold medal game, which will take place Sunday afternoon at Carioca Arena. Each of the semifinal losers, however, will play prior to the championship for the bronze medal.

Team USA, the only team to escape pool play with a perfect record despite issues defensively and poor shooting at times, is considered the heavy favorite to win gold for the third consecutive Games. The squad is loaded with NBA All-Stars, and despite narrow victories over the Australians, Serbia, and France in the group stage, the U.S.’s talent and head coach Mike Krzyzewski’s strategies have been enough.

Yet, even with the likes of Kevin Durant and Carmelo Anthony, the U.S. has proved vulnerable early in games and hasn’t truly played like the juggernaut some expected. That leaves the door open for an upset either in the semis or the final.

Led by former Real Madrid head coach Sergio Scariolo, Spain battled back after suffering two losses to start the tournament, but also features NBA talent in Pau Gasol, Ricky Rubio, and Nikola Mirotic, and has played suffocating defense in Brazil.

The Spanish are hoping to get over the hump, so to speak, after losing to the U.S. in the championship and settling for the silver medal in London and Beijing.

The Australians, who nearly toppled the U.S., have four NBA players, including center Andrew Bogut, who’s been a force on the interior and has harkened back to his more dominant professional days with 11.6 points, 6.0 rebounds, and 1.4 blocks a contest. Australia also rolls out top perimeter players in Matthew Dellevedova and Patty Mills, who’s the second-leading scorer in the tournament at 21.2 points a game.

The Serbians, like Australia and Spain, are seeking their first gold at the Olympics and enjoying their first appearance since 2004 in Athens. They are powered by the excellent inside-outside combo of seven-foot center Miroslave Raduljica (16.7 points, 63 percent shooting) and 24-year-old and NBA-bound shooting guard Bogdan Bogdanovic’s 14.2 points and 50 percent success rate from three.

It’s important to note, the games will be switching to NBC’s main network, unlike the others which have been shown on NBC Sports Network.

As the semifinals continue, this report will be updated to reflect the final matchup in Rio.

Date: Sunday, Aug. 21

Start Time: 2:45 p.m. ET

TV Channel: NBC