GOAL 

The U.S. national team has made it to the final leg of its pre-Copa America preparations, arriving in this San Francisco suburb on Sunday night, ahead of Friday's tournament opener against Colombia. Three friendlies have come and gone, and now Jurgen Klinsmann will be left with just a few more days to make his final lineup decisions for the kickoff clash.

Just how many decisions are really left to be made? Based on how the two recent friendlies went, and how Klinsmann managed his roster, it appears that many lineup spots are set in stone. Michael Bradley should be a lock to occupy the defensive midfield role in the 4-3-3 system we have seen in recent weeks, leaving Kyle Beckerman on the bench. Brad Guzan was named the starting goalkeeper before training camp began, taking the mystery out of a positional battle Klinsmann couldn't afford to continue during the Copa America.

Realistically there are only a handful of spots truly up for grabs, and as far as the Colombia match goes, even these battles may have already been decided. That said, these lineup decisions are ones Klinsmann will be considering throughout the tournament. Those who aren't chosen to start against Colombia may still get their chance during the group stage.

There are three U.S. positional battles in particular that are setting up to be good ones throughout the Copa America. Here is a closer look:

GYASI ZARDES vs. CHRISTIAN PULISIC

The rush to anoint Pulisic as the savior of American soccer is in full effect, and as much as Pulisic has earned the blooming adoration with impressive form in limited minutes, the hysteria is making it easy for some to overlook the fact he is still very inexperienced.

Zardes has an edge right now because of his physical presence up top, and overall work rate. Klinsmann is putting a premium on fielding a lineup with the defensive capabilities to make things difficult for Colombia, and Zardes covers more ground than any other attacker on the team.

Is Zardes' defensive work really enough to give him the nod over Pulisic? That isn't his only advantage. As fearless as Pulisic looks — and the kid absolutely has the makings of a future star — he has only started a handful of games above the youth level. He showed well in starts for Borussia Dortmund, but he has never started in a meaningful game where his team wasn't the clear favorite.

Does that mean Pulisic couldn't cut it against Colombia? Not necessarily, but Zardes has an experience edge, and defensive qualities that make him more well-suited to help carry out Klinsmann's game plan in the opening match. That said, Pulisic hasn't exactly been a slouch on the defensive side in recent appearances. It is clear Klinsmann has emphasized that part of the job to the youngster. Pulisic has done well to show his ability to contribute on both sides of the ball, which could help lead to a chance to start at some point in the tournament.

ALEJANDRO BEDOYA vs. DARLINGTON NAGBE

Normally, it would seem silly to be questioning whether a player who just had a two-assist game like Bedoya should still be a starter in the next match, but there is no denying that Nagbe has made a very strong case for starting against Colombia.

The Timbers midfielder put together his second straight gem against Bolivia, coming off the bench once again to dazzle with his poise, clean passing and movement. He completed 26 of 28 passes, including the assist on Pulisic's goal. In total, Nagbe completed 59 of 61 passes over the team's past two friendlies, providing a goal and assist.

So why is Bedoya still the choice against Colombia? Experience is key here too. Nagbe has yet to start a national team match, while Bedoya has played in a World Cup and is coming off a strong season with Ligue 1 side Nantes. He has played mostly as a winger during his time under Klinsmann, but he has also spent more time playing in central midfield with Nantes in the past year and has made it clear he prefers playing in the middle.

Sure, there may be some lingering bad taste from Bedoya's disastrous foray into a defensive midfield role against Brazil last fall, but that is in no way the same thing as the two-way central role Klinsmann has him playing in the 4-3-3. That position plays to Bedoya's strengths, and we saw a glimpse of what he can bring to that role against Bolivia.

Klinsmann is angling toward starting Bedoya in the middle on Friday, so he can keep pressure on Colombia's attacking threats in a more consistent way than Nagbe would.

"Ale's role, if it's a wide role or a role more inside, it depends on what system we play, it depends on what is needed, it depends on who we play against and so on," Klinsmann said. "This is always the different pieces that we are discussing up and down because we don't have the luxury to say that we ignore what the opponent is doing and just do what we want. That's not the case.

"We are not Brazil or Argentina or Germany or Spain. We have to have an eye on what Colombia is coming with, with [Juan] Cuadrado or [Carlos] Bacca or James Rodriguez, and then we have to put the pieces together."

Nagbe's strengths, at this point, make him a better option coming off the bench against Colombia, when he could use his attacking qualities to punish a potentially tired Colombian defense. Also, given the amount of work Bedoya would have to put in to try and contain Colombia, Nagbe would be a very good option to start against Costa Rica in the second match.

And what of Jermaine Jones? His starting role seems pretty assured, and with his toughness and big-game experience, it seems extremely unlikely Klinsmann won't have him in the lineup against Colombia. In fact, if there is a game the U.S. needs Jones' bite and attitude in, it is the Colombia match.

JOHN BROOKS vs. MATT BESLER

When Matt Besler left Saturday's friendly against Bolivia at halftime, rather than staying in for some reps in central defense, the message became clear: John Brooks has pulled ahead of Besler, and seems like a lock to start the Copa America opener.

There is some unease about that reality because of Brooks' past shaky outings for the U.S., but this changing of the guard has been inevitable ever since Brooks reestablished himself as a steady regular at Hertha Berlin. Brooks is younger than Besler, equal or better passing the ball, and a more imposing figure on set pieces. Brooks doesn't boast Besler's quickness, or his ability to read situations quickly, but Klinsmann is banking on Brooks learning on the job.

The recent friendlies have shown us a Brooks that is feeling more comfortable than we have ever seen him. His passing has been sharp, and he has been more aggressive. He worked well with Geoff Cameron against Bolivia, even though the two hadn't been partnered together in central defense in almost three years. Sure, Bolivia didn't offer anywhere near the type of test Colombia will, but we saw enough to suggest a Brooks-Cameron tandem is the best one to go with.

The big concern about that pairing is the lack of matches they have had together. Klinsmann didn't sound overly concerned about the fact Saturday's friendly was just their second together in central defense.

"The fact that they haven't played together that often is down to injuries. It's always down to some other issues," Klinsman said. "Finally, they're both healthy, so I think they're fine-tuning things, they develop a good partnership and hopefully that partnership is very valuable."

And what about Besler? We haven't heard the last of him. The Copa America schedule consists of three matches in nine days, and Klinsmann has already made it clear he will be making changes in his lineup to cope. Something else to consider is Brooks has been prone to injuries, so Besler gives the U.S. an experienced and capable backup.

Perhaps the most interesting takeaway from the Bolivia friendly was Besler's impressive showing at left back. Klinsmann wouldn't rule out the possibility of doing it again.

"it depends on who is playing on the right for the opponents," Klinsmann said of the possibility of using Besler at left back in Copa America. "When you talk about certain names then you need to have an idea where, OK, maybe you're not throwing Matt in there because he's a 100 percent pure defender that gets the defensive job done and doesn't need to worry about getting forward that much, so you want to have a more attack-minded left back in there."