Normally an outfielder, the 32-year-old Snyder was promoted from Triple-A Round Rock and will start at first base against the Miami Marlins, batting sixth.
To make room on the active roster, the Rangers placed Moreland on the DL with os trigonum syndrome in his left ankle. Moreland is mulling over surgery options and wants to get a second opinion.
Snyder was put on the 40-man roster after Matt Harrison, who had spinal fusion surgery June 3, was transferred to the 60-day disabled list.
The Rangers have now used the disabled list 19 times this season -- most in the majors.
Snyder was hitting .284 with 18 homers, 11 doubles, 51 RBIs and 81 strikeouts in 232 at-bats at Round Rock.