The Rangers now have 38 players on their 40-man roster, plus four (Alex Claudio, Yu Darvish, Jurickson Profar and Nick Tepesch) on the 60-day disabled list.
Blanks ended the season on the 60-day disabled list following surgery on both feet. He hit .313 with three home runs and six RBIs in 18 games with the Rangers.
Corporan didn't play for the Rangers in the second half following a left thumb sprain. He batted .178 with three homers and 15 RBIs in 33 games with Texas.
Richardson spent the entire year on the 60-day DL, following lower back surgery in March and a broken foot suffered during a Minor League rehab assignment in July.