Loe, 32, posted a 7.09 ERA with 5.1 K/9, 3.4 BB/9 and a 50.5 percent ground-ball rate in 26 2/3 innings for the Mariners, Cubs and Braves in 2013. A bloated 34.4 percent homer-to-flyball ratio was Loe's undoing last season, as it led to an unthinkable 11 homers in those 26 2/3 frames. Loe's career mark is just 13 percent in that category, and the league average was 10.5 percent, suggesting that he's due for some improved luck in that department. Loe isn't far removed from big league success, as he posted a 3.61 ERA in 229 1/3 innings from 2008-12 with the Rangers and Brewers.
Gutierrez, 30, pitched to a 4.23 ERA with 7.3 K/9, 3.3 BB/9 and a 42.6 percent ground-ball rate in 55 1/3 innings for the Angels and Royals in 2013. Formerly referred to as "Juan" rather than "J.C.," Gutierrez has 222 2/3 innings of Major League experience and spent a good chunk of the 2010 season closing for the Diamondbacks, collecting 15 saves in the process.
The 28-year-old Rosario saw the most extensive action of his big league career in 2013, totaling 41 2/3 innings of 3.02 ERA ball for the Giants. His ratios weren't as impressive as his ERA, as he averaged 5.2 K/9 and 4.3 BB/9 to go along with a 44.7 percent ground-ball rate.
All three pitchers in this group will hope to win a spot alongside closer Sergio Romo and relievers Jeremy Affeldt, Javier Lopez and Santiago Casilla, each of whom is a lock for a spot in manager Bruce Bochy's relief corps.