Miley (lat/rib) threw a bullpen session Thursday without issue, Adam McCalvy of MLB.com reports.
Miley was diagnosed in mid-May with a posterior serratus strain near the left side of his rib cage and given a 6-8 week timeline for his return, but the veteran southpaw told reporters Friday that he believes he will wind up spending just four weeks on the IL. That would put him on track to return to the rotation around the middle of June. He had pitched to a 3.67 ERA, 1.13 WHIP and 24:9 K:BB across 41.2 innings (eight starts) prior to the injury.