Goldschmidt, runner-up in National League most-valuable-player voting last season, suffered the fracture when he was hit by a pitch from Ernesto Frieri in the ninth inning of Arizona's 9-4 loss to the Pittsburgh Pirates on Friday.
Goldschmidt leads the league in doubles and extra-base hits, is tied for first in runs, is second in total bases and is third in runs batted in and walks.
Designated hitter Corey Hart was put on the disabled list by the Seattle Mariners because of a bruised right knee.
Hart injured the knee earlier in the week against Cleveland but played against the Baltimore Orioles on Friday night. He's batting .203 with five home runs in 58 games.
Red Sox catcher David Ross is put on the DL
Catcher David Ross was put on the disabled list by the Boston Red Sox because of a right foot injury.
Ross is sidelined with plantar fasciitis, a lingering condition that flared up as he ran out a grounder in the sixth inning Friday night.
A day after getting the victory in his major league debut, pitcher Anthony Ranaudo was sent to triple-A Pawtucket to make room for pitcher Joe Kelly, who was acquired from St. Louis on Thursday in the John Lackey trade and will start against his former team Tuesday at St. Louis.