Watch Now: Kanell and Bell: Mark Cuban on Carmelo Anthony and Team USA (1:31)

Team USA faced its greatest test to this point on Saturday against Greece and NBA MVP Giannis Antetokounmpo, and they passed it with flying colors. The Americans won convincingly, 69-53, and pushed their FIBA World Cup record up to a spotless 4-0. They now stand alone atop Group K and have officially clinched a spot in the quarter-finals of the World Cup. 

Kemba Walker led the way for Team USA with 15 points, but only he and Donovan Mitchell reached double figures. Otherwise, it was not a great game for the Americans offensively. Fortunately, they were stellar on defense. Greece was held to only 32 percent from the field, and in its last two games, Team USA has held its opponents to an average of 49 points. Their offense needs work, but this team will be able to contain the best this tournament has to offer. 

Next on the docket for Team USA? The Brazilian team that first took down Antetokounmpo thanks to a unique defensive strategy. They are 3-1 in the tournament so far, having won their initial group with a 3-0 record, but picked up their first loss against the Czech Republic in the second round. That makes this game absolutely critical for Brazil. If they lose, and the Czech Republic manages to beat Greece, Brazil will be knocked out of the tournament. Team USA faced one desperate team in Greece today and overcame them. They'll need to do the same on Monday when they face Brazil. 

Team USA seemed to be in serious jeopardy after their overtime scare against Turkey. They are far from safe as the best teams in the tournament are still looming, but for the first time, this group looks to be coming together as a team. A 53-point decimation of Japan is one thing, but beating a real threat like Greece is quite another. Team USA may not have the star power it typically does, and their shooting has not been great, but this group is ready to compete with anyone on the world stage. Here are the biggest takeaways after yet another American victory. 

Small-ball is king

Team USA has had success with small-ball lineups in this tournament, but it has never been more pronounced than it was in this game. They spent more than half of this game without a center on the floor. Brook Lopez seems to have fallen out of favor, and Mason Plumlee really hasn't been effective in his playing time. 

Gregg Popovich plays two big men most of the time in the NBA. He has been more open to experimentation in this tournament, but he'll never be known as a small-ball coach. Yet given the success he has had in this tournament with such lineups, one of the most important storylines of the rest of the World Cup will be how willing he is to rely on them. Nikola Jokic, Rudy Gobert and Marc Gasol could be awaiting him in the near future. Popovich is going to have to pick a direction in facing them. Right now, his best choice seems to be playing small. 

Defense wins championships

American teams are typically dominant offensively and mediocre defensively in international competition. It is symptomatic of their overwhelming talent advantage. No team can match up with their star power, so they put on a show offensively and rest defensively. Whether its due to a lack of star power this time around or the presence of Popovich as their head coach, this year's American squad has been the opposite. 

In their past two games, Team USA has held its opponents to 38-of-128 from the field. But their offense sputtered against Greece. They themselves shot only 36 percent from the field and made only seven-of-30 three-point attempts. That will have to improve against the tournament's best teams, but Popovich knows firsthand just how far a great defense can take a team. 

The rotation remains jumbled

Sooner or later, Team USA is going to have to trim its rotation. Miserable weather conditions in China forced Popovich to play 10 players in this game, but that has been his style all tournament. Assuming Jayson Tatum returns to the fold, the only player who seems to have been ruled out of consistent playing time is Lopez. 

It is unclear who Team USA's best players are. It changes on a game-to-game basis. But if this team is going to establish a cohesive offensive identity, it needs to make a commitment one way or another. No American player topped 28 minutes in this game. Depth is valuable, but once they reach the knockout stage, production matters above all else. 

Shooting is a major problem

Team USA is shooting only 32.8 percent on three-pointers so far in this tournament. That number is jarring. On this roster, only Mason Plumlee has shot below that mark from three-point range in his career. Whether it is differences in the ball, the stadiums they are playing in or their roster, Team USA has to start making its shots if it plans to win this tournament. Serbia is shooting 47.8 percent from long distance. That gap is too big to bridge with defense alone.