Whalen gave up three runs (two earned) on five hits while striking out one in 2.0 innings during his spring debut against the Rays on Monday.
The 23-year-old was shut down last September with a shoulder issue after struggling to a 6.57 ERA across 24.2 innings, although he did miss bats at a solid rate (9.1 K/9). He got off to a slow start in spring training but will look to turn things around and compete for a bullpen job in 2017.