Arizona Diamondbacks general manager Kevin Towers made several offseason changes, but Arizona still enters this season with numerous question marks, with the bullpen chief among them.
A roster overhaul was needed after a 65-97 record in 2010, especially to a bullpen that posted a 5.74 ERA. Not only was it more than a full run worse than any other team last season, but according to the Elias Sports Bureau it was the sixth-worst bullpen ERA in the divisional era (since 1969), and the worst by any National League squad.
Highest Single-Season Bullpen ERA Divisional Era
Putz was strong in relief with the Chicago White Sox last season, although he was not used much in save situations (3 saves, 4 blown). Putz was above the league average in many categories last season, and most importantly, he finished off batters when he needed to. When Putz had two strikes against a hitter, according to Inside Edge, he converted an out 85 percent of the time, 12 percent higher than league average. That was also four percent better than any Diamondback pitcher last season.
Putz was also very economical, as 54 percent of opponent plate appearances ended in three pitches or fewer (MLB average was 45 percent). Compare that to Gutierrez, who only had 44 percent of his plate appearances last three pitches or fewer. Putz also did a better job of keeping the ball in the ballpark, allowing only four home runs in 54 innings. Gutierrez allowed 13 in 56 2/3 innings – the most among pitchers who threw fewer than 60 innings. Left-handed batters also had an OPS of .721 against Putz, a significant upgrade from Gutierrez’s .927. Gutierrez remains in the Arizona bullpen for this season, but in a less prominent role.
Putz used fastballs to his advantage last season, utilizing the pitch 63 percent of the time. He relied on his heater when he was behind in the count -- 84 percent of the time in those situations. It proved wise, as 70 percent of his fastballs were strikes, 6 percent above league average. His strike percentage on offspeed pitches was lower (63 percent), and only 2 percent above the MLB average.
While Putz's opponent average against fastballs was .265, it was significantly better than Gutierrez's (.294), as well as several other Arizona relievers in 2010, including Sam Demel (.291), D.J. Carrasco (.285) and Aaron Heilman (.293).
Chase Field is a very hitter-friendly venue (ESPN Park Factor ranked 9th last season), so adding Putz to the closer role makes sense. According to Baseball-Reference.com, Putz was able to force grounders more than fly balls last year: 27 percent fly ball hits allowed, compared to 39 percent on the ground. That's crucial if a player wants to have success in a hitter-friendly park.