The Pirates claimed Diaz off waivers from the Marlins on Tuesday, Craig Mish of SportsGrid.com reports.
The 26-year-old has landed in a spot where he could have a realistic path to playing time, as his primary competition at first base and designated hitter will be players like Ji-Man Choi (elbow) and Miguel Andujar. Nothing in Diaz's track record thus far suggests he deserves regular playing time at a key offensive position, however. In 112 career major-league games, he's hit .181/.227/.340.