If the Union’s enthralling 1-1 tie with Los Angeles FC on Saturday was the first time you watched Mark McKenzie, you might never have guessed that he’s only 20 years old.

But if you’ve watched him a lot, you knew what you were seeing — and you knew it was the latest proof that McKenzie has big-time potential.

McKenzie was one of the Union’s standout performers in the game, delivering the best performance of his professional career to date. Though the box score said he recorded just one tackle, one interception, three clearances and one block, the eye test said a lot more. He and Kai Wagner finished tied for the most completed passes of any Union defender on the night, with 38 each.

The quality of the opponent factors into the eye test, and there’s no more fearsome attack in MLS than LAFC’s. Their 77 goals scored this year is over 20 more than any other team. Carlos Vela has a league-leading 28 of them, Diego Rossi has 15 (the fourth-most leaguewide), Adama Diomande has 8 and Latif Blessing has 6 from midfield. All four of them started Saturday, as the visitors loaded up to try to snap a three-game winless skid.

McKenzie was a big reason why that winless streak now stands at four. His positioning, passing, speed of foot and speed of thought were all top-notch. He even pitched in a shot, sending a header of a corner kick in the 61st minute just over the crossbar.

“You’ve just got to be tuned in at all times,” he said afterward. “Every team I’ve been on just reiterates that: know what you want to do before the ball gets to you. It can feel difficult at times when you’re in the back and things open and close so quickly, but just taking a [mental] picture before you even get it helps a lot.”

Those words will be music to the ears of Union manager Jim Curtin. U.S. under-23 team coach Jason Kreis might have heard them too, after having McKenzie at a training camp last weekend to prepare for Concacaf’s Olympic qualifying tournament. Perhaps they’ll even get to U.S. senior team coach Gregg Berhalter, who demands his team play out of the back as a principle (sometimes to a fault).

McKenzie, who has been to one senior U.S. camp so far, probably isn’t ready for Berhalter’s squad just yet. But Saturday night showed he’s clearly on the way there.

“That’s a big boy game, you know, that’s the best way I can put it,” Curtin said. “Those are the real games that if you’re a real player you want to be part of. They feel different, the speed is different. … I’m really happy that Mark got to play in it, and not just play it but also leave a big impact.”

If you’re the sort of person who keeps odds on which Union academy product will be sold abroad first — and rest assured there are many such people — you’ve probably had McKenzie atop the list a few times this year. At other times, you probably didn’t, especially when injuries sidelined him in the spring and appendicitis derailed his under-20 World Cup campaign.

A performance like Saturday’s against a team like LAFC vaults him up right back toward the top. Centerbacks with passing skills are prized assets in Europe. And while there are no hints of whether McKenzie has suitors right now, it’s easy to imagine him joining the cavalry of American rising stars in Germany. The style of play fits him, and the success there of players like Christian Pulisic, Tyler Adams, Weston McKennie and Josh Sargent has Bundesliga clubs paying close attention to America.

“His ceiling is is incredibly high,” Curtin said. “He’s got the combination of, of speed, and physicality, and also really good feet to break lines with his passes.”

The Union know it, LAFC now knows it, and it might not be long before a lot more teams know it, too.