Diaz has been activated by Triple-A Indianapolis.
Diaz was a reserve for the Pirates in case Francisco Cervelli was forced to miss more time, but Cervelli returned to the Pirates lineup on Friday. Therefore, Diaz will go back to Triple-A Indianapolis where he will start tonight against Toledo. The 25-year-old is hitting .267 in 60 minor league at-bats with High-A, Double-A and Triple-A.