Before he ever stepped onto the RFK Stadium field Friday night for his D.C. United debut, Michael Seaton had already made MLS history — the first player born after the league’s inaugural match in 1996.

His first touch in a competitive match perhaps will enter United’s archives as well. Seaton, who withdrew from Central High midway through his junior year to sign with United this past winter, assisted on Carlos Ruiz’s goal seconds after entering and helped the MLS club earn a 1-1 draw with Chivas Guadalajara in a friendly before 12,197.

Ruiz, who began his pro career a year before Seaton’s 1996 birth, scored in the 73rd minute. Chivas, Mexico’s most celebrated club preparing for the start of the Liga MX season, pulled even in the first of three added minutes when Angel Zaldivar headed in Abraham Coronado’s service.

Seaton, who turned 17 in May, was among several debutants for United: Collin Martin, an 18-year-old from Bethesda-Chevy Chase who signed this week, entered in the second half. Newly acquired Luis Silva and Jared Jeffrey started. Andrew Dykstra, the third-choice goalkeeper, made two superb saves in the second half.

Seaton, though, had an immediate impact.

Off a United throw-in, “I thought about it and left it” to roll toward the end line, he said. “I basically threw the defender off-balance, and I see Carlos, and I just crossed it right in as hard as I can.”

The Jamaican-born forward was beaming after the match. His mother was in attendance.

“I wanted to score so bad because I had a happy birthday [undershirt on] for my mom,” he said. “But an assist can work.”

He removed his jersey and flashed the message after the match and spotted her.

“She was telling everyone, ‘Move out of the way, move out of the way, let me see my son!’ ” he said. “She was giving me hugs.”

Seaton has been on loan all season with the third-division Richmond Kickers and will rejoin the USL club Saturday.

“First game, if you play bad or good, it’s still a bonus,” he said. “You learn from it. And then the next game, you play much better.”

“He is a confident kid,” veteran Chris Pontius said. “If he can keep that confidence high, he can be a very effective player. You see the athleticism. He’s young and got a lot to learn, but the sky is the limit for a kid like that.”

Said Coach Ben Olsen: “He has got a long way to go, but that play sums up why he is scoring goals. He has something about him. He doesn’t have a lot of fear in his mind. He goes hard. He is competitive.”

Silva, acquired from Toronto this week, filled a void in central midfield.

“He was just what we thought he was — a guy who thinks differently than some of our players,” Olsen said.

Chivas was missing four players on Mexican national team duty and mixed and matched regulars and reserves. Both teams substituted liberally; Olsen used 11 reserves.

United notes: Reserve midfielder Marcelo Saragosa, who underwent surgery on his right knee in May, had surgery on his left knee this week and will miss four to six weeks. . . . Sheriff Suma, a left-side defender and midfielder from the Sierra Leone national team who most recently played in Azerbaijan, will begin a tryout next week. Guatemalan defenders Cristian Noriega and Jaime Vides, from Municipal, started a tryout this past week.