Castano is expected to be recalled from Triple-A Albuquerque on Tuesday when rosters expand, Kevin Henry of The Denver Gazette reports.
Castano worked to a 3.93 and 1.36 WHIP with 14 strikeouts over 18.1 innings (nine appearances) during his last stint in the big leagues. He'll likely be asked to provide support out of the bullpen once his promotion becomes official Tuesday.