Argentina vs. Ecuador odds, lineup prediction, live stream: Where to watch Copa America online, TV channel

Argentina's quest to win back-to-back Copa America titles kicks into high gear on Thursday, when the knockout stages begin with their faceoff with Ecuador.

The reigning champions are the heavy favorites in this matchup after winning each of their three games in the group stage, but Lionel Messi's fitness is a big talking point heading. Argentina might have enough firepower in attack to survive Messi's absence if he cannot make it, but they will first have to take on an Ecuador side that rescued their Copa America campaign after a rough start.

Here's what you need to know before tuning in.

How to watch and odds

• Date : Thursday, July 4 | Time : 9 p.m. ET
• Location : NRG Stadium -- Houston, Texas
• TV: Fox  | Live stream: Fubo ( Try for free)
• Odds: Argentina -230; Draw +310; Ecuador +750

Storylines

Argentina: Things are so far, so good for the reigning champions, who won all of their games in the group stage and have yet to concede a goal. They have done this with and without Messi, who played in their first two games and assisted Lautaro Martinez's goal against Canada but missed the Group A finale against Peru. Messi was not exactly needed since they had already qualified for the quarterfinals, which afforded head coach Lionel Scaloni a chance to show off his depth. It was a successful trial -- Martinez scored twice, bringing up to four goals so far at the Copa America.

There's no question that Argentina would rather have Messi available than not, though. Many will be encouraged by the fact that he returned to training on Tuesday, but his questions about his availability will linger until the team news drops on Thursday.

Ecuador: Ecuador were placed in a favorable group with Venezuela, Mexico and Jamaica but had to survive a chaotic start to the competition to finish second in Group B. Enner Valencia's red card and their subsequent loss to Venezuela meant they needed results against Jamaica and Mexico, which favored Ecuador since the Concacaf teams were far from their best at the Copa America. Valencia's return will help matters, but the team now has to prove themselves in undoubtedly their hardest test of the competition so far. They will be encouraged by the fact that they held Argentina to a 1-0 win last month in a friendly, but Scaloni opted to rotate that day -- including benching Messi.

Predicted lineups

Argentina: Emiliano Martinez, Nahuel Molina, Cristian Romero, Lisandro Martinez, Nicolas Tagliafico, Rodrigo De Paul, Alexis Mac Allister, Enzo Fernandez, Nicolas Gonzalez, Lionel Messi, Julian Alvarez

Ecuador: Alexander Domínguez, Angelo Preciado, Felix Torres, Willian Pacho, Piero Hincapie, Alan Franco, Moises Caicedo, Kendry Paez, Jeremy Sarmiento, Kevin Rodriguez, Enner Valencia

Prediction

This is Argentina's game to lose and with or without Messi, they will be up for the task. Expect the reigning champions to lean on several attacking players as they pick up their latest victory of the Copa America, and likely pick up a clean sheet in the process. Pick: Argentina 3, Ecuador 0