As the roster currently stands, the Boston Red Sox don’t necessarily need to add any more starting pitchers to their MLB roster for 2022. With Nathan Eovaldi, Chris Sale and Nick Pivetta locked in and tons of depth with new guys (Michael Wacha, Rich Hill, James Paxton eventually) and younger pitchers (Tanner Houck, Connor Seabold, maybe Garrett Whitlock), if the Red Sox do absolutely nothing else before the 2022 season starts once the lockout ends, they have all the makings of a perfectly fine MLB rotation.
With that written, if there is any position that can never have enough depth, it’s starting pitching, which becomes doubly true considering some of the uncertainty surrounding recently injured players like Sale and Paxton. So, if we follow the Red Sox’s pattern so far, maybe it would make sense to take another flyer on a player with some definite issues but who has the potential to be a stalwart if things go right. There are a lot of guys out there who fit the bill, but Danny Duffy is someone who stands out.
Duffy was in the midst of a very good season in 2021 before injuries cost him the bulk of the campaign. From April to mid-July, he was easily the best starter for the Kansas City Royals, even when he missed time from mid-May to late June, posting a 2.51 ERA in 61 innings. Most of his positive production came before mid-May, as he reached five innings in a game only once after returning on June 23.
Pushing the injury concerns aside (for now), when Duffy was on the mound, he was a reliable starter, if not more than that. Although some of his results might have had a bit of a mirage to them considering his less stellar expected ERA (4.24) and expected FIP (4.23), when you consider his park adjusted numbers (57 ERA- and 81 FIP-), it’s tough to be too critical of his work when he was on the field. That is especially true when you consider some of the improvements he made. For starters, he was much less prone to allowing home runs, cutting his home run to flyball ratio to 8.2 percent from 13.7 percent in 2020. It was the first time since 2017 he was below 10 percent.
Duffy also set a career-high in strikeout rate (25.8 percent) while keeping his walk rate right at league average (8.7 percent). Duffy lifted his strikeout rate to a more respectable level by getting a decent number of swings and misses, ranking in the 72nd percentile in whiff rate and the 77th percentile in chase rate in MLB, according to Baseball Savant. Another factor was a rise in his velocity, with his four-seam fastball clocking in at an average of 93.7 miles per hour compared with the 92.2 miles per hour mark he set in 2020 over a similar sample size (56 1/3 innings). The uptick in speed still didn’t have him reaching the levels he achieved prior to 2017, but it was a step in the right direction, especially since his fastball was easily his most valuable pitch.
Duffy finished the 2021 season as the third best starting pitcher for the Royals based on fWAR, but he didn’t actually end the season in Kansas City. Even though he was injured, he had proven valuable enough that the Los Angeles Dodgers took a chance and traded for him at the deadline. Unfortunately for the Dodgers and Duffy, the deal didn’t really pay off, as Duffy remained a spectator for the rest of the season. Still, he got a Dodgers hat, so that’s cool.
The injury issue isn’t something that will likely go away for Duffy. The southpaw just turned 33 in December and with maladies shortening multiple campaigns for him recently, it’s tough to believe his health will improve. When he has been healthy, Duffy has been a streaky pitcher for most of his career. He’s looked like one of the best pitchers in baseball some seasons, while he’s look like a pedestrian back of the rotation starter in others. His career ERA sits just below 4.00 and his career FIP is a little higher than that (4.17). In addition, aside from last season’s sparkling numbers, his run prevention marks have been trending in the wrong direction.
For all the tough times, Duffy has flashed brilliance on more than one occasion. In addition to last year’s strong spring and early summer, Duffy was a two-win pitcher or better in three of four seasons between 2014 and 2017. OK, maybe being a two-win pitcher isn’t brilliant, but it’s still pretty good. Unfortunately, 2017 is a pretty long way away. However, if the Red Sox were to sign Duffy, they wouldn’t be doing so with the expectation of picking up an ace for the top of the rotation; they’d be signing him with the hopes of getting a solid middle rotation arm. And that’s likely what they would get, as Steamer projects Duffy to throw 98 innings with a 4.09 ERA in 2022.
In terms of what a contract might look like, MLB Trade Rumors has Duffy pegged to sign a one-year, $10 million deal for this season, which is exactly what Paxton signed for. Paxton has the higher ceiling, or at least the more consistently high one, having produced at least 3.5 fWAR for four-straight seasons from 2016 to 2019, but Duffy has always been solid and more recently produced positive results. Like Paxton, Duffy will be coming off an injury in 2022 and it’s unclear when he’ll be ready to go, but if the Red Sox’s plan for upgrading the rotation is to buy a bunch of lottery tickets and hope a few hit (rather than trading for a top of the rotation starter or something), then Duffy would fit the mold.