Dodgers manager Dave Roberts said Monday that Diaz (neck) "hasn't been good" on his rehab assignment and "needs to pitch better" before the team considers returning him to the active roster, Sonja Chen of MLB.com reports.
Diaz gave up five runs on two hits and three walks while recording only two outs in his last rehab appearance with Triple-A Oklahoma City on Sunday, and he's allowed six runs with a 4:7 K:BB in 3.1 rehab innings. Diaz has been out since mid-August with neck inflammation, and while his health no longer is a concern, the Dodgers need to see the reliever pitching better before activating him. If/when Diaz does return, he will likely be used in low-leverage spots, at least initially.