The major league record for most hits by a player in a doubleheader is nine, first set by Fred Carroll in the American Association in 1886. The record has since been matched by eight other players, four in the National League and four in the American League.
Rickey Henderson with 130 steals.
Barry Bonds. But IMO, he used steroids and his record should not count.
If you're talking about the Modern Era (1900 to present) then it would be Roger Maris.
That is Ty Cobb who hit .366 (.3664) during a 24 year career from 1905-1928.
Rickey Henderson, with 1,406, shattering the old record of 938 set by Lou Brock
Ted Williams, with 145 RBIs in his rookie year, holds the record.
The record number of hits in a Major League Baseball player in a nine inning game is seven. The record was reached twice, once in 1892 and once in 1975.