For only five years and $110 million, Jordan Zimmermann signed with the Detroit Tigers. In light of the other free-agent contracts signed by starting pitchers this offseason, Zimmermann’s deal is a huge bargain. Having seen the Nationals chase other free agents aggressively, it’s hard to understand why they did not make more of an effort to re-sign Zimmermann.
Nevertheless, he will have to be replaced. Tanner Roark appears to be the first man up for the task. In 2014, he was pressed into duty and gave the Nationals 198.2 innings of 2.85 ERA pitching. Not bad. Instead of riding with Roark in 2015, the Nationals went out and signed Max Scherzer to a record-breaking contract. Without a clearly-defined role, Roark regressed to a 4.38 ERA, working long relief and making spot starts.
Roark’s low ERA in 2014 was fueled more by a bit of luck than dominant pitching. His low BABip of .273 was roughly 10-percent below league average. His higher ERA in 2015 was fueled by some bad luck. His GB/FB ratio went up, but so too did his percentage of fly balls leaving the yard. Roark is a pitch-to-contact type, and dominance should not be expected. He was better in 2014 than the numbers would have predicted, and worse in 2015. Something in the middle this year should tide the Nationals over until Lucas Giolito and A.J. Cole arrive in the big leagues.