Time for the main event

Each year the Copa Libertadores treats South American soccer fans with excitement of the highest order, rivaling -- and in many cases, surpassing -- that of Europe's Champions League.

This year will be no different. The continent's most prestigious club competition kicks off Tuesday night and it promises thrills, chills and the unexpected.

Last year's winners, Boca Juniors, who trounced Grêmio of Porto Alegre 5-0 on aggregate in the finals, have dominated South American soccer in recent years. And although Boca is expected to challenge for the title again this year, there are several other clubs that look equally strong.

The likes of São Paulo, Cruzeiro and River Plate all have enough talent to win the competition, which would seem to reinforce the trend of Brazilian and Argentine clubs ruling the continent. But we see a break this year.

Even though only two clubs from outside the Big Two have won the tournament in the last 16 editions, the recent emergence of exciting clubs --Colombia's Cúcuta Deportivo, Uruguay's Defensor Sporting and Paraguay's Libertad -- seems to indicate that this year's champion could come from elsewhere.

Traditionally, the quality of the competition has been of a very high standard, and recent trends suggest that the globalization of soccer means that soon the Argentine and Brazilian domination could be over.

But for now, clubs from those two countries are still a cut above the rest. Even their smaller clubs, such as Copa Sudamericana champ Arsenal de Sarandí, have proven their worth lately. Here's a rundown of what we can expect from the 49th edition of the Copa Libertadores:

There are a number of incredibly even-matched groups in this edition of the Libertadores, but the group that stands out from the rest is Group 5, featuring River Plate, Club América, Universidad Católica and Universidad San Martín.

Obviously, River and América are expected to advance from the group, but both clubs will be fought all the way by a Católica side which has improved enormously in recent years. San Martín, which was founded only four years ago, is the outsider at this stage, but may raise some eyebrows after winning the Peruvian Apertura championship in style last year.

Why will River Plate top the group? The Argentine powerhouse did extremely well in the Argentine preseason, and seems to have found a new effective style of play under former Argentine international Diego Simeone. One player to keep an eye on is highly rated Uruguayan international Sebastián Abreu. El Loco has now played for 13 different clubs in his career and was one of River's stand-out performers during the preseason.

These are the kinds of matches everyone wants to see at this early stage of the competition. And the best thing about it is that this year, fans will be treated to several outstanding clashes between exciting teams that could go all the way.

Probably the biggest of them all is the showdown between River and América, two teams who have enough ammunition to fight for the title. Both teams are traditionally amongst the top two sides of their respective nations, Argentina and Mexico, and both legs should be a thrill to watch.

Another exciting clash will be the one between San Lorenzo and Cruzeiro. Whenever Argentine and Brazilian clubs meet in competitions of this magnitude, things always get heated. The best thing about this meeting is that both teams are well-respected in their leagues, but haven't won any international hardware in a number of years. Both will be desperate to get things right this year.

Next best is the dual between São Paulo and Atlético Nacional de Medellín. With the reining Brazilian and Colombian champions up against each other, top-quality soccer is a guarantee. Brazilian clubs have actually struggled against their Colombian counterparts in recent years, but this strong São Paulo squad should have the upper hand this time around.

Other dream matchups include clashes between Boca Juniors and Colo-Colo, and Flamengo and Nacional of Montevideo, clubs that have won a combined total of 11 titles. Meanwhile, Brazilian sentimental favorite Santos, currently languishing near the bottom of the 20-team Paulista state championship, will surely have it tough against Cúcuta Deportivo, last year's exciting revelation team.

If we had to pick only one from the 32-team field, it would be São Paulo, which has reinforced itself with loads of talent. Not only did the the Tricolor Paulista get Adriano on loan from Inter Milan, but it also brought in Carlos Alberto from Werder Bremen, Fábio Santos from Lyon and defenders Joílson and Juninho, both from Botafogo.

São Paulo is the most complete squad in the competition, and if the Brazilian champions are able to get together an attractive game plan, they should sweep aside all opposition in the group phase. Expect Richarlyson to provide the inspiration -- the highly rated midfielder is destined for worldwide stardom. São Paulo is definitely this year's team to beat.

Last year, Colombian outsider Cúcuta Deportivo shocked everyone in reaching the semifinals, where it lost out to eventual winners Boca Juniors.

But this year's surprise might be Fluminense, which has made several important purchases, such as that of Darío Conca, Leandro Amaral, Gustavo Nery, Dodô and Washington. Flu has found itself in the shadows of Rio rivals Flamengo and Vasco da Gama over the years, but this year is its opportunity to explode on the international stage (SI.com's Tim Vickery wrote last week about Flu's controversial three-striker experiment). Other possible revelation teams include Danubio and Lanús, who will both take part in Group 2.

With his amazing potential coupled with São Paulo's overall depth, Adriano is a good candidate to finish as the competition's leading scorer. "The Emperor" (a nickname he hates), has regained his nose for the goal in the Paulista championship since joining São Paulo, and has shown flashes of his all-time best. If he's able to rediscover his top form in time, there's no way anyone will be able to beat him to the Golden Boot.

Other players who are expected to score plenty are Radamel Falcao García of River Plate, Salvador Cabañas of Club América (last year's top scorer) and the always reliable Martín Palermo of Boca Juniors.

The old powers are the obvious candidates: Boca, River, São Paulo and Santos. But this year there could also be surprises from Paraguay, Uruguay and Colombia.

Libertad has consolidated itself as one of the best teams in South America in recent years, as has Uruguayan power Nacional, which won two international friendly tournaments on home soil in the last couple of weeks.

Colombia's chances lie with Atlético Nacional, but the 1989 Libertadores champs will need to be in top form to come out of a group that consists of extremely difficult opponents in São Paulo, Sportivo Luqueño and the winner between Audax Italiano and Boyacá Chicó in Tuesday's final qualifier.

History has clearly shown that besides the traditional South American powers, less fashionable clubs from Argentina and Brazil usually do very well in the Libertadores.

Look out for San Lorenzo as it tries to mount a strong title challenge, with a much improved squad. El Ciclón beat River Plate to the signature of Andrés D'Alessandro, who will boost its already impressive midfield.

Another team not to be counted out is Juan Sebastián Verón's Estudiantes de La Plata. La Brujita recently told the press that before he retires, his ultimate desire is to help Estudiantes win the Libertadores for the first time in 38 years. Then, perhaps, we may see Verón's long-awaited move to Major League Soccer before he hangs 'em up.

Cruzeiro, which won the Libertadores in '76 and '97, demonstrated its overall depth with a comfortable 6-3 aggregate victory over Cerro Porteño in the qualifying round, and it and '81 winner Flamengo will surely stir some trouble.

Meanwhile, Mexico's two best-supported clubs -- Chivas de Guadalajara and Club América -- should also be extremely stiff opposition, as they strive to win a South American club competition for the very first time.

Boca Juniors playmaker Juan Román Riquelme has revealed his obsession with the Libertadores, and if he continues his sensational form of last year, there's no doubt Boca will reach the decisive stages of the competition yet again.

After losing the final of the Club World Cup to AC Milan in December, Boca has a lot to prove to its demanding fans, and will surely be a serious title candidate.

But so will archrival River Plate which, for once, seems to have a squad that is capable of winning the title. Sadly, a Boca-River superclásico grand final is out of the question -- the South American federation has ensured no two teams from the same country can meet in the decider.

But São Paulo should be around for the decider. The Tricolor Paulista will be a very classy unit, and could well win its fourth title, especially if Adriano works his magic.

Cruzeiro and Santos also promise to deliver. But the team that could surprise everyone is San Lorenzo, which finally seems worthy of winning its first-ever Copa Libertadores.