The 2013-14 CONCACAF Champions League gets underway without one familiar team: Monterrey. The three-time defending champions did not qualify for the tournament, missing out on their chance at a four-peat when they were eliminated in the semifinals of the Liga MX Clausura Liguilla.

With Monterrey out of the picture, the tournament is wide open. The title of CONCACAF's best and a spot in the Club World Cup are on the line, but there is little reason to believe anyone can challenge the dominance of the Mexican clubs.

MLS has made gains in recent years, winning groups and, last year, seeing the Seattle Sounders become the first MLS club to eliminate a Mexican club over two legs, but once again, it was an all-Mexican final. Teams from south of the border have won eight straight CONCACAF championships and all five since the group stage format was introduced. This is Mexico's tournament, at least until someone proves different.

Group 1

Arabe Unido vs. W Connection- A year ago, W Connection pulled off two massive results when they drew both Xelaju and Chivas at home. The latter came on the penultimate match day, too, and kept the Mexican giants from the knockout stages. But as memorable as those two results were, they were the only two results the club got and they never really challenged for a spot in the knockout stages. If the club is to do better this year, they will need Joevin Jones to have a breakout tournament. The 22-year-old had 10 goals in the TT Pro League last season, but now he has to perform on the continental stage.

Arabe Unido has not been in the tournament since 2010-11, when they didn't make it out of the group stage, but they did qualify for the quarterfinals the previous year. Like W Connection, they have an uphill climb in the group, with the Houston Dynamo as the favorites, and almost certainly need to take all three points at home if they want to have a chance of making the knockout stages.

Group 2

Real Esteli vs. Sporting Kansas City- With Olimpia also in in Group 2, Real Esteli and Sporting KC landed in one of the tournament's tougher groups. That's a familiar position for Real Esteli, who were grouped with Tigres and Alajuelense a year ago. Unsurprisingly, they only managed one point.

Sporting have no experience in the Champions League, but Graham Zusi, Matt Besler, Benny Feilhaber, Claudio Bieler and Kei Kamara have played enough matches in hostile grounds that they shouldn't be fazed by going to Central America in this competition. The question is whether Peter Vermes' pressing style translates to the continental game, where there will be shaky refereeing, raucous crowds and any number of weather-related obstacles. Sporting's struggles in the MLS Playoffs don't exactly inspire confidence in their ability to get results in this competition.

Group 3

Valencia vs. Herediano- After winning their group and advancing to the quarterfinals a year ago, Herediano are flying high coming into this year's competition. They bested Real Salt Lake in the group stage with an impressive draw at RSL on the final match day to finish top of the group and a runner-up in the Costa Rica Primera Division only gives them more confidence this year.

Like every Haitian club before them, Valencia are mostly fodder for the competition's biggest clubs. With Cruz Azul also in the group, they will be lucky to scrape a single point, but at home against Herediano will be their best chance.

Group 4

Sporting San Miguelito vs. Club America- With Monterrey out of the picture, America are one of the tournament's favorites this year. Their dramatic win in the Liguilla final last season earned them the Liga MX title and had they brought that same team back this season, they would be the heavy favorites, but the departures of Christian "Chucho" Benitez and Diego Reyes left them weaker at the front and back.

Sporting open the competition with two home matches, which they will need to get at least four points from to have any chance of advancing. Unfortunately for them, with America and Alajuelense in the group, that appears to be a dream too big.

Group 5

Montreal Impact vs. San Jose Earthquakes- Ever since Toronto FC made their debut in MLS, the Canadian Championship, and the Champions League spot that accompanied it, has been all theirs. But last year, the Impact finally got the best of them and wrested away Canada's spot in the Champions League. it just so happens that this year, Montreal are one of MLS's best teams too.

Things don't look as bright for the Earthquakes. While last season was as much, if not more, of a breakthrough for them as it was for the Impact, they have slumped this season. Now they take on an Impact team that is better than them in most positions, but especially in the middle where Patrice Bernier has been fabulous. Unless Chris Wondolowski can conjure up some magic, the Impact look like the favorites in this group.

Group 6

Toluca vs. Caledonia AIA- Group 6 is Toluca's to lose. Caledonia proved a year ago that they don't have the horses for the Champions League when they took just one point and Comunicaciones is short on goal-scoring threats. That leaves Toluca as the heavy, heavy favorites.

Pablo Valezquez is off to a hot start this season and Toluca have taken points form each of their last three matches. The only question when they host Caledonia is how seriously they take the match and how many goals they win by.

Group 7

Luis Angel Firpo vs. Tijuana- Like Toluca, Tijuana should have no problem with their group. Dagoberto Portillo and rising defender Xavier Garcia give Firpo a decent defense, but they have little else and Victoria were well behind Olimpia last season in the Honduran Liga.

Meanwhile, Tijuana showed well in the Copa Libertadores and thanks to the addition of Dario Benedetto, haven't missed the departed Duvier Riascos too much. The jury is still out on Jorge Almiron, but the start of the season has gone fine and if he proves to be out of his depth, Firpo and Victoria won't be the clubs to do it.

Group 8

Isidro Metapan vs. Cartagines- The Champions League hasn't been kind to Metapan. While this will be their sixth consecutive appearance in the competition, they have only once made it out of the group stage and that came in 2011-12 when they were put in one of the competition's weakest groups. There's little reason to believe that will change this year either, not after finishing fifth in the Primera Division and failing to make the playoffs.

Cartagines were the surprise club of the Costa Rica Primera last year, challenging for their first league title since 1940 and while they fell short, they did qualify for continental competition for the first time since 1994. There is little in the way of big names on the team, with Randall Brenes being the lone regular for Costa Rica.

The L.A. Galaxy should be the favorites in Group 8 and if either Metapan or Cartagines is going to challenge them, they will likely need four points in their two matches against the other. That battle for four starts on Match day 1.

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