The United States were proactive in their Copa America Centenario opener. But they weren't very good. And now, with their tournament lives on the line against Costa Rica, they need to make the leap. They need to sort out their problems. They need to find the spark that was missing against Colombia or they will be out of the competition in embarrassing fashion.

The Americans need Darlington Nagbe. And they need Christian Pulisic too.

This isn't exactly a revelatory statement. Both have been on the tip of fans' tongues for months and the clamor for their move to the starting lineup has been getting louder with each match.

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Nagbe is a mature creator who was pegged as a future star for the U.S. years ago, blessed with the skill and vision that the Americans have long lacked. All that stood between him and the national team was citizenship, which he got last fall, and he's spent much of the last eight months doing nothing to put a damper on the hype.

Pulisic wasn't even in the conversation for the national team when Nagbe got his first cap last November, largely on account of him being 17 years old and never having played a professional match. But his career took off in January when he made the Borussia Dortmund first team and he spent all of 2016 playing regularly for one of the best teams in Europe, scoring goals and showing no fear or intimidation in front of gigantic crowds while breaking through with the national team. Now he stands on three caps and, like Nagbe, has a goal to his name too.

The two of them are skillful and creative players. They are calm and smooth on the ball, capable of running by defenders and unlocking opposing teams from the middle of the pitch as well as in the final third. And that's exactly what the U.S. needed against Colombia.

While the U.S. kept possession in their Copa America opener, they got few chances. At halftime they had more than 60 percent of the ball and not a single shot on goal. They played narrow, which DeAndre Yedlin attributed to the threat that the Colombian wingers posed, but it was clear that the Americans simply didn't have the players who could unlock a defense content to let the U.S. have the ball.

Clint Dempsey was made a lone central striker, which he's never been suited to. Bobby Wood was isolated on the wing, unsure how to create that far from goal and Gyasi Zardes' constant running on the other side of the field didn't do much good against a team that was content to let him have the ball and slow the match down. Alejandro Bedoya and Jermaine Jones are both tireless workers and good two-way midfielders, but neither is going to play a killer pass.

So when Colombia sat back, especially after the second goal, the U.S. passed the ball around plenty, but never really bothered their opponents. It was static as the Americans played in tight spaces, looking for the creative play on a team lacking creative players.

Nagbe and Pulisic can change that. They can be that spark, that coolness on the ball, that ability to find space and cause problems both with and without the ball.

With at least Nagbe on the team, the U.S. will have a creative hub and a player who is comfortable dropping team, pressing up higher, moving the ball and forcing opposing defenses to both track and step to, opening space for his teammates at worst and making killer passes at best. Pulisic can add some dynamism on the wing, while also operating as a threat to cut in. And together, as we saw on the goal they combined for against Bolivia last week, you have a duo that can play one-twos, dribble at players, time and weight passes well, then finish.

Klinsmann has long promised a proactive team and he deserves credit for doing everything in his power tactically to deliver on that against Colombia. The U.S. spent most of the match dictating to Los Cafeteros, with the ball and with numbers flying forward, but that approach condenses the field and requires players who have both the vision to see space, create space and then exploit it, with and without the ball. To take the next step forward, the U.S. needs the players to make that attitude and those tactics pay off.

The alternative is that they abandon the proactive style, don't push their fullbacks forward, look to dominate the ball or dictate the match in favor of a hyper pragmatic and reactive, counterattacking approach. But considering Klinsmann is in Year 5 and was tasked with instilling a style to go along with results, doing so is probably out of the question. They need to do what they did against Colombia, but do it better.

Playing Costa Rica, a team nowhere near as good as Colombia, will help the U.S., but they also need to help themselves by using the players who can play in tight spaces, challenge defenses and turn that possession into chance so Klinsmann's dreams have a chance of becoming reality. They need Nagbe and Pulisic.

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