Kevin Durant feels the key to the United States' confidence-boosting win over Iran at the Tokyo Olympics was down to becoming more selfish and playing with freedom.

Team USA's 25-game winning run in the men's basketball at the Games was ended by France last week but they responded with a 120-66 victory against Iran on Wednesday.

That loss to France followed exhibition defeats to Australia and Nigeria in the build-up to the event, leading to questions over the cohesion of the record 15-time gold medallists.

But Gregg Popovich's side answered those critics against Iran with a comprehensive victory in which they played fast, aggressive basketball throughout.

Damian Lillard, one of those to come in for heavy criticism following the opening-game defeat, top-scored with 21 points, all from beyond the arc.

USA knocked down 19 3-pointers and 22 of their 37 shots (62 per cent) inside the arc as they showed signs of the quality that has taken them to three successive gold medals.

Brooklyn Nets forward Durant insists the chemistry of the side was never in question as he highlighted the changes made between matches.

"After a tough loss last game, today we came out with more freedom as individuals and took the shots that we normally like to take," Durant said.

"They went in tonight, and we guarded up, so it was a good step.

"I felt like we were in sync last game, but like I've been saying, it's a make or miss game today.

"We created good shots last game and I think today it's the continuity of what we've been doing over the last week. We finally capitalised on the stuff that we've been working on.

"Like I said, our chemistry has been great since day one. We're all excited to be here, I mean this is the Olympics, this is the national team. 

"But I think we were a bit too unselfish early on and tried not to step on toes. That bit us before.

"Tonight the guys came out there and were super aggressive to look for their shot but also keep everybody involved, and we were able to make some shots. 

"Damian came out, got it scorching for us, so we're going to need that going forward."

Head coach Popovich rotated his roster against Iran by bringing in Jrue Holiday and Devin Booker, who were brought off the bench against France.

"In the last game we have to play two 'bigs' and I think that might have clogged it up a bit for us all offensively," Durant added.  

"Defensively we've been solid the whole time, but offensively we were trying to find our rhythm. 

"I played the four [position], so I was able to stretch the floor a bit and give guys space and we were able to get some confidence and knock some shots down."

A victory over the Czech Republic on Saturday will guarantee the world's top-ranked side a place in the quarter-finals.

That next match will also provide Durant with his next opportunity to surpass Carmelo Anthony as USA men's basketball all-time Olympic top scorer.

Durant managed 10 points against Iran, moving him to within five of Antony's record (336).

Team USA star forward Kevin Durant remains bullish about the side's ability to adjust their game in their pursuit of a gold medal at the 2020 Tokyo Olympics.

USA were beaten 83-76 by France in their opening game at the Tokyo Olympics having been beaten by Australia and Nigeria in exhibition games in the lead-up.

The losses have led to criticism of the cohesion of Team USA who are 15-time Olympic gold medalists, but Durant insisted there was no panic ahead of Wednesday's second group game against Iran.

"Our adjustment is we just make more shots," Durant said. "We've got the best talent in the world on the team."

USA led throughout the first half against France before collapsing down the stretch, surrendering a 74-67 advantage.

"We got each other good shots," Durant added. "We know how to play off each other."

USA assistant coach Lloyd Pierce reiterated Durant's calmness about the situation, stating they need to remain confident.

"The keys to beating these guys is just being ourselves, worrying about what we do best," Pierce said.

"We want to get out and play fast and create extra possessions throughout the course of the games.

"It's only 40 minutes, we have to make this game a little bit faster and get as many easy shots as we can.

"We have to be ourselves as well. Our guys have to play with confidence, have to play with the freedom they're used to, they also have to do that together, make simple plays, quick plays and enjoy the experience."

Brooklyn Nets forward Durant provided a positive assessment of the impact of Khris Middleton, Jrue Holiday and Devin Booker who played against France after competing in the NBA Finals last week.

The trio arrived barely 48 hours before the France game, with Holiday top scoring with 18 points plus four assists from 27 minutes.

Booker shot poorly, with four points and three assists from 18 minutes, while Middleton only had five minutes of game time.

"What they did to me felt like just who they are," Durant said. "I always have a high-level respect for all three of those guys.

"For them to come out and play, not really complain about anything, be excited to be here [full credit]. Those guys are amazing talents, it's great being around them."

The United States saw a 25-game winning streak in men's basketball at the Olympics come to an end as they were beaten by France in their first outing at Tokyo 2020.

Team USA arrived in Japan looking to strike gold for a fourth straight Games, yet their build-up had been anything but straightforward. Exhibition defeats to Australia and Nigeria raised concerns before travelling, while COVID-19 protocols ruled out Bradley Beal and Kevin Love was replaced at late notice by JaVale McGee.

Still, a squad including Kevin Durant, Damian Lillard and Jayson Tatum – as well as Khris Middleton and Jrue Holiday from the Milwaukee Bucks, the newly crowned NBA champions – saw the reigning champions listed as favourites.

France, though, caused an early upset at the start of the tournament. Evan Fournier starred with 28 points to help his team triumph 83-76 at the Saitama Super Arena.

There were wins for Australia and Italy too on Sunday, as well as a victory for the Czech Republic.

Big names come up short in shock defeat

Team USA had rounded out their build-up to the Games by beating Spain, yet there will be concerning signs for head coach Gregg Popovich following a flat performance against France.

They were successful with just 41 per cent of their two-point attempts and landed only 10 of the 32 shots put up from beyond the arc. Despite the shooting issues they still led 45-37 at half-time, only for the game to turn in a third quarter where they mustered a paltry 11 points.

Durant finished up with 10 points on 4-of-12 shooting, while Lillard had 11. The latter's slip that caused a turnover in the closing seconds when down by four rather summed up a disjointed performance from the entire roster, leading to a first loss at the Olympics since going down to Argentina at Athens 2004.

Devin Booker, who had helped the Phoenix Suns reach the NBA Finals, landed only one of his six attempts from the field, with Holiday (18 points) finishing as the USA's leading scorer having only joined up with the team on the day of the game.

Also in Group A, the Czech Republic recorded an 84-78 victory over Iran.

Ingles impressed, but Nigeria come up short

Nigeria had defeated both Argentina and the United States ahead of the Games, raising hopes of making an impact in Japan.

However, able to knock down just 29 per cent of their attempts from deep, they struggled to keep pace with Australia, scoring only 27 points in the entire second half as they went down 84-67.

Still, Joe Ingles – who had 11 points for Australia – praised the Nigerians for their display, particularly on defense as they forced 21 turnovers. Patty Mills was the leading scorer in the game, finishing with 25.

"You have to give a lot of credit to Nigeria, with how they played and the style they play," Ingles said. "They are up and in, they are athletic and get up the floor, and they obviously have a great coach [in Mike Brown].

"I think a lot of people underestimate the team and the country. They are a really good basketball team."

Meanwhile, Italy opened their Group B campaign with a 92-82 victory over Germany. Simone Fontecchio led the way with 20 points, including landing all five of his three-point attempts.

Ali Daei congratulated Portugal captain Cristiano Ronaldo for equalling his long-standing record for international goals.

Ronaldo scored twice from the penalty spot to move onto 109 goals for defending champions Portugal as they secured passage to the knockout stages of Euro 2020 with a 2-2 draw against France on Wednesday.

The 36-year-old Ronaldo now needs just one more goal to surpass Daei, who chalked up his remarkable tally for Iran between 1993 and 2006.

Daei was quick to mark the achievement on social media and predict that he will not jointly hold the record for long.

The 52-year-old wrote on Instagram: "Congratulations to @cristiano who is now one goal away from breaking the men’s international goalscoring record. 

"I am honoured that this remarkable achievement will belong to Ronaldo - great champion of football and caring humanist who inspires and impacts lives throughout the world.

"Vamos!"

Ronaldo's first opportunity to claim the outright lead will come when Portugal contest their last-16 tie on Sunday.

Having finished third behind France and Germany in Group F, Fernando Santos' side will take on Group B winners Belgium in Seville.