James Rodriguez, Eduardo Vargas
 

The Copa America Centenario is down to its final three teams. Lionel Messi and mighty Argentina are through to the final after knocking off the United States, 4-0. The second semifinal match features Colombia, No. 3 in the world, against No. 5 Chile, at Chicago's Soldier Field. Here's a primer:

Player To Watch

Eduardo Vargas

Colombia: David Ospina

After spending a year in the shadow of superstar Petr Čech at Arsenal, the Colombian goalkeeper has shined as José Pékerman’s first choice. Ospina has conceded just a single goal in the tournament, winning all three of his starts. He rested during Colombia's 3-2 group stage loss to Costa Rica. He was particularly sensational in the team’s quarterfinal game against Peru when he made a clutch save on Miguel Trauco in the penalty shootout.

Chile: Eduardo Vargas

The forward, who plays for Bundesliga power 1889 Hoffenheim, is coming off the best game of his international career. An astounding four-goal effort, including three in a span of 13 minutes, demonstrates how lethal Vargas can be. With six goals (tournament leader) and one assist in four caps this tournament, Vargas is the leading candidate for the Golden Boot. A victory in Chicago would help his case.

Biggest Question Mark

Colombia: Health of James Rodriguez

James Rodriguez

The 2014 World Cup Golden Boot winner finds himself in exactly the same role as he did in Brazil: Facilitating, catalyzing and, at times, spontaneously manufacturing Colombia's offense. But after colliding with U.S. midfielder Michael Bradley in Colombia's opening victory, Rodriguez left with a shoulder injury. Rodriguez has played since, but his health is still a concern. The striker must be fully fit and in his best form for the Colombians to reach the final.

Chile: Dealing with Arturo Vidal Suspension

The Bayern Munich midfielder is missing the semifinals after getting a second yellow card in the quarterfinals. Without Vidal empowering the Chilean backline with his tackling ability, or orchestrating on offense with his ability to pass and shoot at a world class level, Chile will be in for a tough match.

X-Factor

Colombia: Declining Confidence

The international soccer powerhouse only just survived its quarterfinal contest versus Peru -- currently No. 48 in the world -- on penalty kicks. In a game Colombia should have won easily, its offense was anemic and it could not beat Peru goalkeeper Pedro Gallese. Colombia mustered only one shot on goal in 120 minutes. A quick goal for Colombia on Wednesday would settle nerves. Conceding an early goal could crush it.

Arturo Vidal

Chile: Surging Confidence

If it is the worst of times for Colombia, it is the best of times for Chile. The 2015 Copa America champions decimated Mexico, 7-0, at Levi’s Stadium in Santa Clara on Saturday. Along with the four goals from Eduardo Vargas, the Chileans got two from Edson Puch. Arsenal star Alexis Sanchez made the score sheet, as well, with a goal. Chile is as confident as a squad could possibly be, and overconfidence might be the biggest problem.

More Soccer:
-- Twitter Loves Michael Bradley's Rainbow LGBT Armband
-- Rival Soccer Fans Sing 'Dancing Queen'
-- What Does FIFA's New President Mean For The Future Of Soccer?