Chafin (shoulder) injured his groin during his rehab assignment at High-A Visalia, Nick Piecoro of AZCentral.com reports.
Manager Chip Hale said that Chafin tweaked his groin, so his return from the DL may be delayed. Chafin had been pitching very well at Visalia, having thrown four hitless innings over four games, walking two batters in that time. Further news on his recovery and expected return should be known in the coming days.