The Diamondbacks designated Diaz for assignment Sunday.
Diaz gave up his spot on the 40-man roster to right-hander Jose Cabrera, whose contract was selected from Triple-A Reno ahead of his first MLB start Sunday versus the Twins. After making eight appearances for Arizona over the previous two seasons, Diaz turned in a disastrous performance out of the bullpen in his return to the big leagues. He retired just two of the 10 batters he faced in Saturday's 16-8 loss, surrendering seven earned runs on seven hits and one walk before being lifted from the contest.