Rocky Mountain high

Good summer to be a ball fan in this place, says PECOTA. Getty Images

As pitchers and catchers arrive in Florida and Arizona, Baseball Prospectus will be previewing every division in MLB. Today: the NL West and AL West.

The National League West is coming off a relatively strong year; its five teams collectively posted the league's top winning percentage (.519) of any of the three National League divisions.

The Los Angeles Dodgers (who won the division), Colorado Rockies (who advanced to the playoffs as a wild card) and San Francisco Giants all won at least 88 games. As 2010 dawns, the division finds itself in relatively tight economic straits, with none of its teams making much of a splash in the winter free-agent market. That's really nothing new; these teams feature relatively strong player-development systems and a host of talented young players, which enabled them to do as well as they did with the lowest average payroll of any division at an average of $86 million. Depending upon how various personnel decisions shake out as the spring continues -- including late signings -- any of the top four teams might challenge for the title.