The 32-year-old Villanueva spent the 2015 campaign with St. Louis, where he worked in a multi-inning relief role, logging 61 innings across 35 appearances. With the Cardinals, he worked to a very strong 2.95 ERA with 8.1 K/9, 3.1 BB/9 and a 42.4 percent ground-ball rate. Villanueva stranded an inordinate amount of baserunners, prompting sabermetric ERA estimators like FIP, xFIP and SIERA to peg him more for an ERA in the mid- to upper-3.00 range, so a repeat of that sub-3.00 ERA might not be something Padres fans should count on. He’ll also most likely be moving to an inferior defensive club, although on the flip side, he’ll be moving to a more pitcher-friendly home park.
Villanueva could compete for a rotation spot or a reprise his bullpen role with the Padres, as he has experience in both capacities. However, if he’s to assume the role of long reliever/swingman, that would seem to make Odrisamer Despaigne a somewhat redundant piece. Despaigne soaked up 125 1/3 innings for the Padres in that capacity last season, although he also posted a sky-high 5.80 ERA and saw his strikeout rate drop considerably in his second season of Major League action.