Team doctors examined Cruz and gave an initial diagnosis of a muscle strain near his chest. They sent him to Del Webb Medical Center for further examination to rule out anything more serious than a muscle ailment.
The Rangers later said in a statement that several tests were negative and Cruz was being released after a stress test, which general manager Jon Daniels said he passed.
Cruz can resume baseball activities as early as Saturday.
Daniels said Cruz's status for the World Baseball Classic will depend on how he feels Saturday. Cruz was set to leave Sunday to join the Dominican Republic for the WBC.
"I think our guys made the right call," Daniels said. "Better safe than sorry to have him checked out."
Cruz is hitting just .214 in spring training but leads the team with five RBIs.
Ron Matejko covers the Rangers for ESPNDallas.com. Information from The Associated Press was used in this report.