As someone who has played in LIGA MX and is now playing in MLS with Atlanta United, Greg Garza has a unique understanding of the history made on Tuesday when New York Red Bulls and Toronto FC advanced to the semifinals of the CONCACAF Champions League.

Just two times in the knockout rounds of the competition had an MLS team advanced at the expense of a Mexican team in the long history of the tournament.

New York Red Bulls advanced by hammering Tijuana 3-1 at Red Bull Arena to take the two-game aggregate 5-1. Toronto lost at Tigres 3-2 and tied 4-4 on aggregate goals, but advanced because it scored two away goals at Estadio Universitario.

“I think that it shows this league is growing,” Garza said, who played for Tijuana. “I saw a couple of tweets out there that league is no longer a retirement league. I think a lot of people used to put that emphasis on this league. They can start brushing that away.

“People who thought that we were so far behind before, we are definitely cutting that margin.”

MLS isn’t done.

Seattle will play Chivas tonight. It defeated the Mexican powerhouse 1-0 in the first leg at CenturyLink Field.

That loss sparked one newspaper in Mexico to use this headline: “Es Insolting & Unacceptabol.”

Garza said the results in the tournament are improving because young talent in MLS is improving, citing Atlanta United’s Miguel Almiron and Josef Martinez as examples of a trend within the league’s 23 teams.

“It helps the league grow in a way and also provides competition for the domestic guys,” Garza said.

The Red Bulls’ goals last night were scored by Tyler Adams, a 19-year-old Homegrown signing, Marc Rzatkowski, a 28-year-old native of Germany on loan from Salzburg, and Kaku Romero Gammara, a 23-year-old Designated Player from Argentina.

“I have the feeling that this league is getting better and better, and from year to year,” Atlanta United midfielder Kevin Kratz said. “It would be interesting to see some more games against other countries to see where we are right now with where this league is.

“On the other side, the way the league is set up and the way it’s developed the last couple of years, I think it’s a very good sign for U.S. soccer that you can see that you can compete with other countries on a high level and be successful.”

With last night's results, nine MLS clubs have advanced to the semifinals of the tournament since 2008-09, according to MLSSoccer.com. Just two, Real Salt Lake in 2010-11 and Montreal in 2014-15, advanced to the finals. Real Salt Lake defeated Saprissa 3-2 across two games and Montreal eliminated Alajuelense 4-4 on away goals across two games. Real Salt Lake advanced but was beaten by Monterey 3-2 in the title game. Montreal was beaten 5-3 by America in the title game.

The CONCACAF Champions League was first played in 1962 as the Champions’ Cup. In that iteration, D.C. United (1998) and L.A. Galaxy (2000) were crowned champs.

The tournament’s name was changed in 2008.

Teams from the CONCACAF region -- North America, Central America and the Caribbean  -- are eligible to compete in the tournament. Pachuca is the reigning champ. Club America has won it the most times (7).

This season, five MLS teams qualified. Seattle made it as the 2016 MLS champs. Dallas made it as the 2016 MLS Supporters Shield champs as well as being the ’16 U.S. Open Cup champs, New York Red Bulls qualified as the 2016 Eastern Conference champs, Colorado qualified as the ’16 Supporters Shield runners-up and Toronto qualified as the ’16 Canadian Cup champions.

This year’s tournament was reduced in size from 24 teams to 16 and the elimination of group stage games.

The 2019 edition of the tournament will undergo more changes.

From MLS, the 2017 U.S. Open Cup winner (Sporting KC), the U.S.-based team with the best aggregate record over 2017 and ’18 seasons, ’18 MLS Cup winner, ’18 Open Cup winner and ’18 Canadian Championship winner will be eligible to compete. In the aggregate race, Atlanta United trails NYCFC by two points.