Broxton obviously has tremendous stuff at a closer but I'm not surprised to see him struggle even if he flourished roughly the last two years as a setup man. His location and pitch selection can be amiss at times. Sometimes, he'll throw a slider and it's not dipping enough to cover the bottom of the strike zone and consequently it's hit for a single. Dead red fastball and the location is either up or in the hitter's wheelhouse and it's struck hard.
Also keep in mind that setup and/or closing situations have been hard to come by for the Dodgers until this recent 3 week stretch or so. Broxton is making more appearances, sometimes pitching back to back. He might not be quite used to that in terms of this year.