Should Rocco Rios Novo became a starting goalkeeper for Atlanta United, or some other first division club, he may owe a debt of thanks to Ezequiel Barco and Brad Guzan.

It was Barco’s inadvertent pass backward through Atlanta United’s defense in its Champions League game at Alajuelense that forced Guzan to come sprinting out of his box. As he attempted to play the ball he collided with an Alajuelense player. A yellow card -- the ref pulled that out first -- was changed to a red in the 43rd minute with the score tied 0-0.

Off came Guzan. Alec Kann, Guzan’s backup for the past four seasons, is recovering from offseason surgery and didn’t make the trip. Ben Lundgaard wasn’t on the game-day roster. On came the 18-year-old Rios Novo, who was supposed to be basically a spectator because he signed a four-day contract to join the team from Atlanta United 2 on Monday.

“I just felt a lot of happiness, and it’s a moment I’ll never forget,” Rios Novo said.

Rios Novo made six saves and must have felt like the bull’s-eye in a shooting gallery in the final minutes because he kept finding the ball to preserve Atlanta United’s 1-0 win.

He said his best save may have been his first when he dove down to his right to stop a hard free kick. He couldn’t handle the shot cleanly, but recovered to jump on the loose ball just as two Alajuelense players arrived. One of them inadvertently made contact with Rios Novo’s head, forcing him to stay down until the trainers could examine him and Heinze could figure out if there were any other players who could put on the gloves.

“It was a very difficult game with all the circumstances in the game,” he said. “Going down a man in the first half and play the whole second half down a man. The team didn’t have any other option but to come together like that, and it was a difficult game.”

Rios Novo showed his range of developing skills: He caught two more hard shots that were at him, he was forced to quickly change direction from left to right to stop another shot, he came out of his goal once to block another shot, and punched away yet another.

Rios Novo joined Atlanta United 2 on loan from Lanús on March 2. He was the starting goalkeeper for Argentina during the U-17 World Cup in 2017 and the South American U-17 Championship in 2019. Rios Novo had five shutouts in eight matches in 2019 to help Argentina win its fourth South American championship.

It is likely that Rios Novo will start the second leg of the series Tuesday at Kennesaw State. Guzan can’t because of the red card. MLS teams are allowed to sign a specific player to four, four-day contracts during the season. Rios Novo sounded like he will be ready.

“I think all of my previous experiences can only help me,” he said. “Whether it was experiences in youth World Cups, or other matches in Argentina or in the friendlies here during preseason. I think it’s especially important for a goalkeeper to get minutes, so all of those experiences helped me up until this point.”