FC Dallas make their first appearance in the tournament after last year's run to the MLS Cup final, while Toronto FC return after their third straight Nutrilite Canadian Championship title. Both FCD and TFC qualified after winning their respective two-leg qualifying round. Pumas UNAM of Mexico City are the group heavyweights after winning the 2011 Mexican Clausura. At the other end of the spectrum are Tauro FC, Panama's most decorated club and potential group spoilers.
Location: Frisco, Texas, USA
Home stadium: Pizza Hut Park (21,193)
How they qualified: 2010 MLS Cup runners-up
Previous CCL appearances: None
Profile: FC Dallas started 2010 as an afterthought, but put together a 19-game unbeaten run midseason then got hot again and made it all the way to the MLS Cup final. They're lightning-quick on the counter thanks to speedsters Brek Shea and Marvin Chávez, and in Kevin Hartman have one of the best pure shot-stoppers the region has ever seen. They're coming off a long, hard, hot July, but sit second in the Supporters' Shield race and just added another key piece in Maicon Santos.
Player to watch: Daniel Hernandez
The defensive midfielder and captain, Hernandez is an extension of everything going on in Schellas Hyndman's noggin from the first whistle to the last. He won't win many foot races, but he's one of the smartest players around and controls the geometry of the game in a way few can match.
Location: Toronto, Canada
Home stadium: BMO Field (23,000)
How they qualified: 2011 Nutrilite Canadian Championship winners
Previous CCL appearances: 2 (2009-10, 2010-11)
Profile: Toronto FC underwent their annual midseason facelift in July after winning their third straight Canadian Championship. It looks like it's paid off, as youngsters Peri Marosevic and Eric Avila have blended with veterans like Torsten Frings and Danny Koevermans, launching TFC on their best run of form since last season. They'll play wide-open, attacking soccer every chance they get, hitting from angles and trying to get Koevermans — the lethal Dutch veteran — looks in front of net.
Player to watch: Peri Marosevic
Toronto got Marosevic after he'd been waived by fellow Group C participants FC Dallas. The former US youth international has made good on that faith, scoring twice already and generally making a nuisance of himself in the penalty area. He has a goalscorer's instincts, someting TFC badly missed eariler in the year.
Location: Mexico City, Mexico
Home stadium: Estadio Olimpico Universitario (62,700)
How they qualified: 2011 Mexican Clausura champions
Previous CCL appearances: 2 (2008-2009, 2009-10)
Profile: Pumas are one of the most storied teams in the Mexican Primera División, and one of the three big teams in Mexico City along with Club América and Cruz Azul. It was la Máquina that denied Pumas in the CCL quarterfinals back in 2009, and then did so again in the semis a year later. They're a solid favorite to get to that stage or beyond in this year's event, thanks to a clever midfield and an attack that likes to keep the ball on the ground and interchange as much as possible. They're unbeaten in their first five games this season in Mexico as of Aug. 16, putting them atop the standings so far.
Player to watch: David Cabrera
Cabrera, who's recently broken into the ranks of the full Mexican national team, has been a revelation in the central midfield over the past year. He doesn't put up prolific numbers, but he works both sides of the ball, rarely commits turnovers and keys the classic Mexican passing game Pumas employ.
Location: Panama City, Panama
Home stadium: Estadio Rommel Fernández (1,000)
How they qualified: 2010 Panamanian Apertura champions
Previous CCL appearances: 2 (2008-09, 2010-11)
Profile: Tauro FC are the most decorated team in Panamanian history, collecting eight titles in their brief existence. They were founded in 1984 by Italian industrialist and Juventus fan Giancarlo Gronchi, which should tell you all you need to know about their style of play. They'll keep men behind the ball, try to to counter at every opportunity and steal any scoreless draw they can get their hands upon.
Player to watch: Juan Pérez
Pérez, a 31-year-old defensive midfielder and former Panamanian international, will be the man tasked with making sure Tauro keep their shape against faster, better, more experienced teams. If he's overrun, they'll be overrun.