The diagnosis that Joe Mauer has pneumonia, likely ending the catcher's season, was the latest in a long line of injuries and illness that have sidelined the former batting champ and MVP this season:

Mid-December, 2010: Undergoes minor surgery on his left knee, the same knee he had surgery on in 2004.

Feb. 18: He isn't ready to catch when pitchers and catchers report and receives injections of Supartz, a solution that helps lubricate and create a cushion in knee joints.

March 16: Plays in his first spring game -- as designated hitter. He catches two innings in a minor league game the next day.

April 14: Comes down with a viral infection before a game at Tampa Bay. That night the team places him on the disabled list with what it describes as "bilateral leg weakness.'' Mauer subsequently visits the Mayo Clinic for a variety of tests that he says found nothing more serious than leg weakness.

June 2: Catches three innings -- his first appearance behind the plate since April 12 -- in an extended spring game at the Twins' Fort Myers minor league complex.

June 17: Returns to the Twins lineup for the first time since April 12.

July 27: Hits his first home run of the season; he has just three homers total.

Aug. 23: Strains his neck playing first base and is out for a week.

Sept. 2: Misses the first of two games because of an upper respiratory infection.

Sept. 16: Is diagnosed with pneumonia, likely ending his season.