Alvarado (shoulder) was playing catch at Tropicana Field on Friday, Marc Topkin of the Tampa Bay Times reports.
The 25-year-old was shut down from throwing Aug. 19, but he's returned been cleared to resume playing catch. Alvarado was shifted to the 45-day injured list in early September and won't be able to return before the end of the regular season, but he could rejoin the team for a potential playoff run.