After an exhibition circuit where they demolished opponents by an average of nearly 27 points a contest, Team USA is beginning to build the same aura of invincibility associated with the great Olympic squads of the past. Don't let that number fool you, however, as there is a very real possibility the Americans could find themselves on the wrong end of the scoreboard when the real competition begins this Saturday.

Despite a star-studded roster and some impressive scorelines, the U.S. has shown enough shortcomings during the build up to the Olympics to cause concern. While their talent eliminates any chance of teams like China, Great Britain or Nigeria from pulling off a miracle upset, there are squads in the field capable of exploiting a poor showing from Team USA.

We'll take a look at the four teams with a realistic chance to turn the American's golden dreams into a nightmare.

1. Spain
If you're looking for high level talent outside of Team USA, Spain's your team. Its roster contains nine players with ties to the highest level in professional basketball. Serge Ibaka, Jose Calderon, Rudy Fernandez and Marc and Pau Gasol all finished the 2012 season on an NBA roster. Guards Sergio Rodriguez and Juan Carlos Navarro have spent time in the league while young forward Victor Claver will be starting his NBA career this upcoming season with the Trail Blazers. The Rockets also hold the draft rights to backup guard Sergio Llull, another player with the potential to contribute to a NBA team.

So despite missing NBA rookie sensation Ricky Rubio, Spain has more than enough talent to take down the Americans, even on one of their better nights. And before you put too much weight into Spain’s lopsided defeat at the hands of the U.S. Tuesday afternoon, keep in mind that not only did the team play without a key cog in Marc Gasol, but they also lacked a real incentive to pull out all the stops to get a win.

Key Player: Pau Gasol. Pau, even at 32, is still one of the best big men in world. Against a U.S. team lacking size, Pau will have to be dominant both on the block and on the glass if Spain is to pull off the upset. Despite the success of his brother Marc in Memphis, the elder Gasol will still be the driving force for Spain.

Wild Card: Jose Calderon. The Gasol brothers are no doubt the country's most talented players, but Calderon might be the most vital. While lauded for his shooting ability, it is Calderon’s knack for avoiding turnovers that will be his most important trait in a matchup against Team USA. Calderon must be able the protect the ball and get the team into their offense against suffocating pressure from the U.S possession after possession.

How they'll win: Calderon, Fernandez, Navarro and Llull take turns safely navigating Team USA's full-court pressure. A clever use of zone in combination with Marc Gasol's underrated ability to control the defensive end of floor force the U.S. to beat them with jump shots. On the offensive end of the floor, the Gasol brothers must overpower a size-challenged roster both on the glass and on the block.

2. Brazil
As one of two teams to put a scare into the U.S. during exhibition play, Brazil has showcased once again it is not to be taken lightly. With a deep, versatile and talented frontcourt of NBA-caliber big men Nene, Tiago Splitter (Spurs) and Anderson Varejao (Cavs, at right), Brazil has the muscle to make things tough on the interior. The squad's biggest problem is its lack of perimeter depth outside of sensational point guard Marcelo Huertas.

Key Player: Huertas. Huertas would likely start on more than half the teams in the NBA where his vision and passing accuracy would be rivaled only by the likes of Rajon Rondo, Steve Nash and Chris Paul. In the earlier matchup, Huertas knifed through pressure and challenged Team USA's defense every minute he was on the floor. The Brazilian pick-and-roll savant holds the key to any upset bid.

Wild Card: Alex Garcia. Leandro Barbosa is more recognizable name thanks to his NBA background, but Garcia is easily the most important wing on the team. While still an offensive factor, Barbosa would have trouble guarding a traffic cone at this point in his career. Garcia, however, is a much more accomplished defender, winning numerous Defensive Player of the Year honors in the Brazilian professional league. If his stroke from the outside holds up, Garcia will be an incredibly valuable two-way force should the teams clash again in the medal round.

How they'll win: Young Raul Neto was thrown into the fire during exhibition play turned the ball over five times in just under nine minutes of action. Neto is unlikely to see the floor if the two teams battle again but the problem is those minutes have to go somewhere. Barbosa will likely slide to the point during the short stretches Huertas is on the bench, but he must be effective during that time as Huertas can't be expected to play heavy minutes against the onslaught of pressure the Americans will bring. Brazil will also need its wings to make shots from the outside and their big men, particularly Anderson Varejao, to keep the U.S. out of the paint.

3. Russia
Russia is a darkhorse to not only knock off the U.S., but perhaps even win the gold. The Russians lack notable names (just one player finished the 2012 season on an NBA roster) but play extremely well as a collective unit. That is thanks not only to their continuity but the excellent guidance they receive from head coach David Blatt, one of the more brilliant tacticians outside of the NBA. This team is tough, will execute on both ends of the floor and possesses enough talent (Andrei Kirilenko, Viktor Khryapa, Timofey Mozgov and Alexey Shved) to give the Team USA a run for its money on the right night.

Key players: Kirilenko and Khryapa. These two form a 1-2 punch that Russia sorely needs in order to pull out a win against the U.S. Kirilenko, the former Utah Jazz star is easily the most talented and accomplished member of this national team. Despite his one-year hiatus from the NBA, Kirilenko still plays at a high level. The long-limbed Kirilenko is a perfect foil for Kevin Durant, though he will no doubt spend stretches marking Carmelo Anthony and LeBron James as well in an attempt to slow down Team USA's offense. Khryapa has dropped off most fans radars (if he was ever on them to begin with) since leaving the NBA in 2008. Vladimir Spivak, a Russian basketball blogger for, has followed Khryapa since and clues us in on the state of his game:

"Khryapa is amongst the best point forwards in Europe these days and pairs incredibly well with his friend and long-time national team partner, Kirilenko. He sees the court very well, effortlessly finding cutters when stepping outside and receiving ball on the perimeter. He can also shoot the 3 (41.4% in Euroleague play last season for CSKA Moscow) very well too."

Wild Card:Shved will carry an immense burden against Team USA. Anton Ponkrashov, Russia's nominal starting point guard, has a history of shaky decision-making and that doesn't bode well against a swarming defense. It will likely fall on the playmaking, but turnover prone, Shved to navigate the pressure and put Russia's offense in a position to succeed.

How they'll win: Blatt and Shved take center stage with their performances. For Shved, that means taking care of the basketball and making steady, and at times spectacular, plays for the Russian offense. Blatt, meanwhile, must come up with a gameplan that includes a mixture of clever offensive sets that turn the Team USA’s pressure scheme against itself while mixing up trapping and zone looks to keep the U.S. out of rhythm all game long on offense. Kirilenko doesn't have to star as long as his defensive effort prohibits one or more of James, Anthony or Durant from doing so. Reserve forward Sergei Monia having a career game launching 3's from the corners wouldn't hurt either.

4. Argentina
Argentina's aging core and limited depth pose problems, but it is an experienced group that certainly won’t be lacking confidence against the U.S. It will be quite the story if this team can find enough gas in the tank to pull off a historic upset.

Key Player: Manu Ginobili. There isn't much about Ginobili that hasn't already been said. He's crafty as ever, accurate from long-range and holds the key to Argentina's upset (and medal) hopes in his hands. An injury or foul trouble for Manu certainly quashes any hopes for a win against Team USA.

Wild Card: Luis Scola. Thanks to Andres Nocioni's decline, there is nary a productive big man on the Argentinean roster outside of Scola. He will have to man both frontcourt spots effectively for well over 30 minutes to provide any hope for the Golden Generation to add one more accolade to its already sterling legacy.

How they'll win: Grit. It seems as though from a personnel and tactics standpoint, there is very little Argentina can do to shift the odds in their favor. It may come down to simple willpower. The aging core will likely be playing extended minutes and have to play productively through the fatigue. Just like an old prize-fighter, they will have to answer every attempted knockout blow from Team USA with one of their own ... and hang around just long enough to steal the game at the end.

-- Brett Koremenos is the editor at NBA Playbook and a contributor to Hoopspeak. Follow him on Twitter @BKoremenos.

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