MEXICO CITY, Mexico -- The Liga MX semifinals get underway Thursday, with two distinct pairings set to determine the finalists in Mexico's Apertura 2012.Relative newcomers Club Tijuana and Leon, the last two teams to ascend to the top flight of Mexican football, will do battle for one final spot, while storied Mexican clubs America and Toluca square off for the other.

The action starts Thursday night in Mexico City with the first round of the America-Toluca fixture, at the Estadio Azteca. The match-up features two ten-time Mexican champions looking to rekindle past magic after a couple years of mixed results.

America looks to make the final after reaching the semifinals of the Clausura 2012. Led by Colombian international Aquivaldo Mosquera, Miguel's Herrera's team boasted the stingiest defense of the regular season, allowing only 15 goals in 17 matches for a club that has been improving all year long.

"This year in football terms, since I arrived at America, a year ago, has produced very good results," Herrera told media ahead of Thursday night's match. "In terms of turning around what was going on at America, we've gotten to two semifinals, we qualified from both tournaments, as the team that's had the most points, the best defense, and the second best attack.

"Twice our center forward has been the goal scoring champion, but none of that means anything if the numbers, even if they're good, don't lead to a championship."

America has won only two titles since the Mexican league went to the short tournament format, lifting the trophy in 2002 and 2005. Toluca, to the contrary, has been one of the more successful clubs in the short tournament era, winning seven of its ten titles since 1998, the latest coming in the 2010 Bicentennial.

That was also the last time Toluca made the Liguilla, which means this season has been one of redemption for the high-flying Red Devils. Head coach Enrique Meza led Toluca to the top of the table in the regular season, and after cruising past Chivas in the quarterfinals, it is clicking on all cylinders as the prohibitive favorites to add to their title haul.

"He's a coach that's been in the national team, and has achieved things," Argentine defender Diego Novaretti said of Meza. "For all the players, he's been strong, very good, and when you know you have a very good coach, you're willing to work the way he wants."

Whichever of the two historic franchises advances will face a less laurelled but no less in-form club, as the other side of the bracket features a pair of newcomers to these stages of the Liga MX Liguilla. Leon enjoys a long history that includes five titles - though just one since the 1950s - but the Guanajuato side only made it back to the Liga MX this year after a decade-long absence from top flight football.

Club Tijuana, for its part, has only existed since 2007, but has risen through the ranks of Mexican football at an incredible rate, becoming one of the more successful Mexican clubs of the last few years. The Xolos have now topped their 2012 Clausura quarterfinals appearance, with a second place finish in this campaign's regular season and a pass to the semifinal round.

With their latest achievement, the historic qualification to the semis, confidence is at a high point. After eliminating traditional power Monterrey from the Liguilla over the weekend, Tijuana head coach Antonio Mohamed says that his Xolos have even more to give on the road in the Apertura championship.

"This team can still give a little more.You'll see it on the field, we have plenty of motivation," the coach said in his post-game comments after 1-1 tie in Tijuana sent the local team through to the semifinals for the first time. "We close at home in front of our people."

The Xolos first must go on the road to Leon, the only team to beat Tijuana during the regular season, winning 4-1 at home. The first leg of that semifinal will be played Thursday at the Camp Nou in Leon, with the return leg scheduled for Sunday night in Tijuana.