Record holder: Jose Pagan, 164 G (1962)
Record holder: Barry Bonds, 73 HR (2001)
Bonds reached that total—an MLB record—with the assistance of performance-enhancing drugs. Testing for such substances has increased under a revised Joint Drug Agreement, and positive tests are met with much stricter penalties.
Record holder: Barry Bonds, .609 OBP (2004)
Within the batter's box, early-2000's Barry Bonds was virtually unbeatable.
Record holder: Christy Mathewson, 4,779.2 IP (1900-1916)
Mathewson spent his career as a member of four-man and even three-man starting rotations to compile those innings. It's now common practice to limit individual workload with a minimum of five starters per team.