Armstrong (neck) is expected to be activated from the injured list sometime this weekend, Marc Topkin of the Tampa Bay Times reports.
Armstrong has been out all season with a neck injury, but he's looked ready on a rehab assignment with Triple-A Durham, holding a 2.00 ERA and 8:2 K:BB over nine innings of work. The 32-year-old is on the 60-day IL, so the Rays will have to clear a spot on the 40-man roster in addition to the 26-man roster.