CARSON, Calif. – Thirteen non-roster players suited up for Chivas USA in Saturday’s preseason scrimmage against UC Irvine, providing new head coach José Luis "El Chelís" Sánchez Solá a look at some of the club's mystery men.

And as it turns out, they may not be so much of a mystery now that their names are emerging. Beyond the five Chivas Guadalajara imports, the list includes a handful of former Chivas USA players, US youth national teamers, Mexican-Americans playing abroad and other MLS cast-offs.

Four of the five confirmed Chivas Guadalajara imports saw minutes on Saturday: 2011 Under-17 World Cup champion Giovani Casillas, defender Mario de Luna, forward José Manuel Rivera and defensive midfielder Edgar Mejía. Goalkeeper José Antonio Rodríguez, 20, did not play.

Nine others, including former Portland Timbers defender Steve Purdy, also saw action. The club has not made any of the trialists available for interviews, but their names were listed on the match stat sheet.

Sánchez Solá has been particularly pleased with what he has seen from the non-roster players in camp.

“We’re waiting to see what we have in the five [Mexican] trial players,” he said. “One or all five might join the group. I don’t have a preference right now. They’re all taking part in a magnificent competition.”

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Casillas, the youngest in the group, scored a goal in seven appearances with Guadalajara in 2011 and found the back of the net three times in the U-17 World Cup, including once in the final against Uruguay. The attacking midfielder made an impression on Saturday.

“Casillas played well,” Sánchez Solá said. “He played about half of what the others did because he’s had a lot of activity in terms of traveling with the national team.”

De Luna, 25, spent the previous six years with Guadalajara. Mejía, 24, is also a product of Guadalajara but was on loan last year with Mexico’s Club León. Rodríguez, who came up with Guadalajara in 2011 and also played for Veracruz, is a member of the Mexican Under-23 squad. Rivera, 26, is a Guadalajara native who spent the last two years in Finland.

Salvadoran international Purdy has been a camp standout, according to Chelís.

“I spoke with him and told him I want him to stay with us,” Sánchez Solá said of the Salvadoran-American. “I want him to stay here. Athletically and team-wise, I vote for him to stay. But he’s obviously got to negotiate with management, and that’s something I’m not involved with. He’s been an excellent player during his trial.”

Other trialists who took part in the scrimmage included: