How the USMNT should line up vs New Zealand in the U20 World Cup last 16 as Kevin Paredes and Rokas Pukstas join the squad

Two latecomers are now in camp as the U.S. finally has a full roster ready to go for the knockout rounds

After a perfect group stage, the United States Under-20 men's national team has now arrived at the part that really counts. As good as their introduction to the World Cup has been, it's been just that: an introduction. The group stage is over; welcome to the knockouts.

Wins over Ecuador, Fiji and Slovakia have propelled the U.S. to the last 16, where they'll face New Zealand on Tuesday. The Junior All Whites topped Guatelama, drew with Uzbekistan and were thumped by hosts Argentina in their own group stage run. The U.S., by all accounts, will be favorites.

Part of the reason for that is that Mikey Varas finally has his whole squad in camp. After starting the tournament down two players - Kevin Paredes and Rokas Pukstas - due to club commitments, Varas navigated the group stage brilliantly, rotating just enough to keep everyone fresh. Now that the cavalry has arrived, the U.S. has a full squad with no injuries or suspensions to speak of.

Now, though, Varas will have some tough decisions. It'll be tough to take some players out of the XI, and it'll be tough to know just how fit several key players can be. And, with one eye on a potential quarter-final match against Gambia or Uruguay, will Varas need to rotate a bit to keep players fresh for the knockout run?

With that said, here's a look at how the U.S. could line up against New Zealand:

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GK: Gabriel Slonina
No need to waste time here and no long explanation is needed. Slonina is the starter and will be for as long as the U.S. are in this tournament. The Chelsea goalkeeper has been fantastic so far, making big saves despite not facing too many shots.

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LB: Caleb Wiley
The first big decision Varas will have to make: who should start at left back? It's between Wiley, Paredes and Jonathan Gomez. We'll go with Wiley, who should be somewhat fresh after coming off the bench against Serbia.
However, just because Wiley is starting, doesn't mean we won't see Paredes and Gomez in this XI...
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CB: Brandan Craig
The Philadelphia Union star may just have been the team's best player in the group stage, so he'll almost certainly keep his spot. The question will be if and when the U.S. can get him rest.
Craig played all 270 minutes in the group stage, and it remains to be seen if he can maintain his high level as this tournament wears on. If he does, the U.S. have a fantastic defender and passer to anchor the backline.

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CB: Josh Wynder
The Louisville City defender has been solid so far, showing why Benfica are reportedly set to sign him in this summer. Varas could stick with the 3-5-2 formation that worked so well against Slovakia, adding Justin Che to the mix, but the best bet is that he goes with the Wynder-Craig pairing for this one.
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RB: Jonathan Gomez
A change due to the arrival of Paredes. If Varas wants to keep his best players on the field, the best way to do so is to put Gomez or Wiley on the right. Gomez should be able to play on the opposite side, leaving Paredes and Wiley to cause absolute havoc on the left.
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CM: Daniel Edelman
The captain should keep his spot in the midfield. The New York Red Bulls product has been strong after being left out of the XI for the opener, with Varas rotating both Edelman and Jack McGlynn out during parts of the group stage. Knowing that, he should be ready to go, giving the U.S. a vital presence in the center of the field.
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CM: Jack McGlynn
If it isn't Craig that's been the Americans' best player, the other option would be his Union team-mate. McGlynn was fantastic during his two starts in the group stage, dictating the game with ease against both Ecuador and Fiji. He was rested for most of the Slovakia win with this game in mind.
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CM: Rokas Pukstas
He's only just arrived, but Pukstas will likely be thrown right into the XI. Fresh off a Croatian Cup win with Hajduk Split, Pukstas has joined the team after missing the group stage. The reason he was included in the roster is because he is, in fact, that good, and the U.S. were willing to navigate the group stage shorthanded just to get him in.
The other option is Owen Wolff, who played all three group games. Even if Pukstas hadn't arrived in Argentina, the Austin FC midfielder could likely do with a rest.
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LW: Kevin Paredes
Like Pukstas, Paredes has also just arrived, having played 24 minutes for Wolfsburg on Saturday. Because of that, he's a slight question mark, but, if he's fit enough to start, he's too good not to.
The addition of Paredes would elevate the U.S. attack to another level. He's done well in the Bundesliga playing all along the left-hand side for Wolfsburg and, like Pukstas, he didn't come all this way to just sit on the bench.
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ST: Darren Yapi
Varas has a big decision here: Does he go with a false nine-sort-of-system once again or does he bring Yapi back? The Colorado Rapids youngster brings more traditional striker play, holding the ball well and bringing wingers into the play. His finishing hasn't been great but, then again, that's been true for his team-mates as well.
Benching Diego Luna is a tough call, but 'Moon Boy' can always come in to change the game as a supersub. Let Yapi play as a No.9, see how the game goes, and then go from there.
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RW: Cade Cowell
The San Jose Earthquakes star was an absolute wrecking ball against Slovakia and must retain his place in the XI. Cowell simply makes defenders uncomfortable, and he gave those on Slovakia's backline nightmares with his performance in that win.
Has he been wasteful? Oh, yeah, but you'll bet on him to keep creating chances. The hope is that he'll put one or two more away and, if he does, the U.S. will be in fantastic shape.