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"We're very happy to get a power lefty out of the bullpen," Avila said on Wednesday evening. "We haven't had that in a long time."
More than a lefty specialist, Wilson has been an effective reliever for the better part of three seasons between Pittsburgh and New York, allowing 158 hits over 199 1/3 innings with 81 walks and 193 strikeouts. He gave up just 49 hits over 61 innings in 2015, walking 20 and fanning 66.
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Left-handed batters hit .236 (17-for-72) with 19 strikeouts against Wilson this past season, but Wilson held right-handed hitters to a .216 average (32-for-148) with 47 strikeouts. He has been statistically more effective against righties than lefties for his career, but Wilson has been stingy against both.
A large part of Wilson's success is a fastball that has averaged 95 mph for three years running, according to Fangraphs. He has complemented that with a cutter, though he has reportedly been working on a breaking pitch to increase his swing-and-miss rate. That said, hitters made contact on a lower percentage of Wilson's pitches this past season (76.3 percent) than in any other year in his career.
"He's a power lefty that can dominate," Avila said. "We feel he can pitch in the back end of the bullpen. He can pitch the eighth inning if needed. At times, he might even be able to pitch in the ninth.
"He's a guy that we don't have in the system. We don't have him in the Minor Leagues. We don't have him at the big league level. He's a power left-handed arm, kind of a dominant type reliever coming out of the chute, and that's the kind of guy we were really excited to have."
The Tigers had been scouring the free-agent market for a lefty reliever, talking with most of the top names and missing out on Oliver Perez, who signed with the Nationals last week. Avila had touched base with Yankees general manager Brian Cashman about Wilson at last month's General Managers Meetings, but the clubs revisited talks over the past week.
"There are other lefties out there that you like," Avila said, "but this is the guy that we like the most and fit best for us, not to mention you have three years of control. His salary structure fits for this year. We're just really excited to have him."
While Cashman wanted to get pitching prospects at the Double-A level or higher, Avila was insistent on not giving up top pitching prospects, and wasn't sure they could reach a deal. Eventually, the two sides agreed on Cessa, Detroit's No. 6 prospect according to MLB Pipeline, and the 19th-ranked Green.
Cessa, acquired by Detroit from the Mets in the Yoenis Cespedes trade, went 8-10 with a 4.52 ERA over 25 starts at three different stops, finishing out the season at Triple-A Toledo. The 23-year-old had just been added to Detroit's 40-man roster at season's end.
The 24-year-old Green, a high-rising prospect a year ago after a breakout season at Class A Advanced West Michigan, struggled with a jump to Double-A Erie, going 5-14 with a 3.93 ERA in 27 starts. His arm, however, earned higher regard than his numbers.
Wilson joins closer Francisco Rodriguez and right-handed setup man Mark Lowe at the back end of a Detroit bullpen that has been revamped since the end of a struggling season for a previously unproven relief corps. Add in starters Jordan Zimmermann and Mike Pelfrey, and a club that had uncharacteristic pitching struggles this past season has added five Major League pitchers in 2 1/2 weeks.