Let's have a real conversation about Team USA.

It has played five exhibition games ahead of the 2019 FIBA World Cup, and there are some warning lights going off. The Americans are low on star power and international experience. Their big men can be suspect, their shooters are inconsistent and their lack of chemistry shows up all the time, particularly during wild turnover binges.

This isn't quite the same, but it is reminiscent of the run up to the 2004 Olympics when the Americans leaked oil on an exhibition journey through Europe on the way to the Athens Games. There were more than a few rumblings leading up to those losses and that bronze-medal finish.

Even Monday morning's 84-68 win over Canada in Sydney was not an impressive performance. Their defensive intensity was improved from their loss over the weekend to Australia, but they didn't make a 3-pointer in the second half -- they were just 2-of-14 in the game -- and had more turnovers than assists, among other issues.

At this point, a handful of countries probably believe they can wrestle the World Cup from the U.S., the two-time defending champ, when tournament play starts this weekend in Shanghai. Earlier this month, Team Serbia coach Sasha Djordjevic said: "Let's let [Team USA] play their basketball and we will play ours, and if we meet, may God help them."

The Australians already have beaten the U.S. The Spanish and the French probably quietly harbor belief too. The Greeks will have the tournament's best player in 2018-19 NBA MVP Giannis Antetokounmpo. And in a 40-minute game, anything is possible.

"We've learned," Team USA guard Donovan Mitchell said, "that this is going to be a dogfight."

Here is why Mitchell and the rest of Team USA lack any real margin for error as this unheralded group prepares for its Sunday opener in Shanghai:

Team USA lacks a proven bailout option

Over the past 12 years or so, whenever the Americans were in trouble in an FIBA event, they had a white-hot star (or three) to bail them out. Kobe Bryant played this role, Carmelo Anthony did too. Kevin Durant, Kyrie Irving, LeBron James and so on.

The Americans don't have that -- at least a guy who has proved it -- to lean on when:

They have a bad shooting night.

One of their heavy hitters is in foul trouble (this happened with Mitchell in the loss to the Aussies).

They have a bad defensive quarter.

The other team gets unusually hot shooting.

This reality requires a sense of urgency the national team hasn't been used to. This is a formula for how gold medals slip away.

Team USA might go only as far as Kemba Walker and Donovan Mitchell take it. Joe Murphy/NBAE via Getty Images

This group is good -- here's why it's not great

OK, now that we've said that, it doesn't mean doom. These FIBA games often resemble NCAA tournament games, in which guard play is vital. The U.S. has the best guards in the tournament: Kemba Walker and Mitchell will easily outplay opponents at times; Marcus Smart, when he gets into shape after his calf injury, is going to get in the heads of the other teams; and Joe Harris might be the best 3-point shooter in the event.

But just like in March Madness, often it is one team with less talent but lots of experience together going up against a loaded but unproven roster. The chalk wins a lot, but the upsets happen in one-game scenarios. In the 2016 Olympics, the U.S. guards were Irving, Kyle Lowry, Klay Thompson, DeMar DeRozan and Jimmy Butler. Those are five All-Stars. This team has one All-Star guard in Walker.

Also consider the shooting struggles. Before Monday's woeful 3-point effort, this group was shooting over 40% from long range in the exhibition games. There's a lot of firepower from Brook Lopez to Harrison Barnes to Khris Middleton, though Middleton has mostly shot poorly so far. They have an array of dangerous shooters. If they hit 40% in any game, they probably will win with some ease.

But if and when they are off, they don't have interior scoring to count on. Walker and Mitchell are a small backcourt by elite standards, and size can bother them. They also don't have great isolation players, though Jayson Tatum shows flashes.

They have worked to remedy this by creating a high-passing offense, but their sharing and assist output has varied wildly -- so count on there being dangerous moments because of it.

Lack of star power but not clarity

Being around the team in the lead-up to the World Cup, there does seem to be an acceptance to these challenges. In the past, the U.S. lost competitions because it didn't respect its opponents or was haphazard in preparation. That does not seem to be the case here.

Coach Gregg Popovich is dead serious about this job and has spent months in preparation. He and managing director Jerry Colangelo typically operate in different spheres in the world of basketball, but from this viewpoint, they have worked together to build an infrastructure that is giving the U.S. the best chance here.

It's no one person's "fault" this is a team with the lightest star power since the Dream Team started. It's a combination of factors, from schedule changes to new rest procedures to injuries to trends.

After a couple of losses in the 2000s, stars were crawling over each other to be part of righting the ship. Now that the team hasn't lost in a major competition in 13 years, the urgency is diminished. It's not cool right now for the biggest names to play, and they look for reasons to skip it. Players are more concerned about the perception of being cut than the desire to win a spot.

This is reality, and it has strained USA Basketball's operation, which had been platinum-level successful. Often in basketball, defeat is the result of a dozen little things going wrong. If there isn't gold on the Americans' necks on Sept. 15 in Beijing, then that might end up having been the case.

But the flip side also can be true: If the 2019 version of Team USA is able to overcome these curveballs and challenges, then this truly will have been an accomplishment. Winning this one is absolutely not a given, and that alone could make it worth more.

That is something everyone associated with the team is very aware of as they head for China.