Its Lebron James!
The Mets do not have a player with jersey number 10 on their 2010 40-player roster.
Wide Receiver Randy Reutershan wore the #40 for the Steelers in 1978. He was the only player to wear that number for the team during the 1970's.
In 2009 it was John Mayberry Jr. OF
Bill Lambeer wore number 40. Current players wearing #40 are: Udonis Haslem, Miami Heat Kurt Thomas, Milwaukee Bucks Jon Brockman, Sacramento Kings
Gayle Sayers is the most famous player to wear number 40. He played for the Chicago Bears.
Click on the link below to see all the players that wore #40 for the Steelers.