Marsh (hamstring) is working out with Double-A Reading and is expected to appear in games with the affiliate this week, Matt Gelb of The Athletic reports.
Marsh was placed on the IL on June 3 with a mild strain in his right hamstring and now appears on the verge of a rehab assignment. The outfielder likely won't be able to return when he's first eligible Thursday, but he should be back with the Phillies within the next week or two.