Who are the best players in Major League Baseball heading into the 2012 season? ESPN formed a panel of MLB writers, analysts and contributors to rank the top 500. The countdown from No. 500 to No. 1 begins March 20 and ends April 3.

The results will be announced on ESPN.com, on Facebook and Twitter (@ESPN_MLB). Fans can use the hashtag #ESPN500 to join the discussion or to follow along.

To compile a top-500 ranking, 34 ESPN experts started with a list of the top 600 players projected to play in the majors in 2012. Using a 0-to-10 scale, they evaluated only the quality of each player for the 2012 season. Players who are expected to miss 2012 with an injury, like Victor Martinez, were not included. But Arodys Vizcaino (No. 376) was included because he was injured after the voting. Ages are listed as of July 1, 2012.

Panelists were polled over the final two weeks of February. Dan Szymborski's ZiPS system, which projects 2012 performance, was used to break ties to the fourth decimal point.