[UNDER-20 WORLD CUP] The Under-20 World Cup has been a launching pad for many of the world's great players: Argentines Diego Maradona and Lionel Messi are two of the many stars who have graced FIFA's oldest youth competition. The 2011 edition begins Friday in Colombia without the United States, absent for the first time since 1995, but with many of the world top young players. Here's a look at five Latin American players to watch ...

CASEMIRO (Brazil). The Sao Paulo midfielder helped Brazil win the South American U-20 championship, which also earned it a berth in the 2012 London Olympics. He is under contract with Sao Paulo until 2015 but he could be headed to Italy soon. Inter Milan, AC Milan and Roma are among the clubs interested in Casemiro, who says he's a big calcio fan. "I often watch Italian soccer," he says, "and my favorite Brazilians playing there are Alexandre Pato, Thiago Silva and Julio Cesar."

ERIK LAMELA (Argentina). At the South America U-20 championships, American-born Michael Hoyos served as the Argentine playmaker in Lamela's absence, but Lamela was recalled for the U-20 world championship after leaving River Plate for Roma. After Argentina's early exit from the U-17 World Cup and Copa America, the pressure will be on Lamela and other highly touted teammates like Juan Manuel Iturbe, Facundo Ferreyra, Roberto Pereyra and Adrian Cirigliano as Argentina seeks a record seventh U-20 title.

DIEGO POLENTA (Uruguay). Born to Uruguay parents in New York but qualified for an Italian passport that facilitated his move to Genoa from Danubio for $2 million in 2008. He is considered one of the top left-sided defenders at Under-20 World Cup. The Celeste U-20s are following on the heels of Uruguay's second-place finish at the Under-17 World Cup and its Copa America title.

JAMES RODRIGUEZ (Colombia). Born in Colombia, Rodriguez began his pro career with second division Envigado FC but moved to Argentina's Banfield at the age of 17. An outstanding 2010 Libertadores Cup campaign earned him a transfer to Porto, which has earned a reputation as one of the Europe's most astute importers of South American talent. Rodriguez came on late in Porto's 1-0 win over Braga in the 2011 Europa League final and scored a hat trick in the 6-2 victory over Vitoria Guimaraes in the 2011 Portuguese Cup final.

ERICK SANCHEZ (Mexico). Sanchez has been compared with Javier Hernandez, debuting with Guadalajara, the same club that produced "Chicharito," at the age of 16 in November 2010, and scoring six goals -- including one against Club America in Mexico's "Super Clasico" -- in the 2011 Clausura.