It's time for the Red Sox to start thinking like a small-market team, because burning money in the name of their rotation could have dire consequences that stretch well into the 2020s.
With Chris Sale, David Price, and Nathan Eovaldi set to earn $80 million annually through 2022 despite being major injury risks, the Red Sox will need to bargain hunt to fill the rest of their rotation. So where might they turn?
The key will be finding undervalued assets. One way to identify them is to look for pitchers with the biggest disparity between their ERA and FIP.
The latter — fielding independent pitching — is an ERA-like number derived from the events a pitcher can directly control: walks, strikeouts, home runs, and hit by pitches, the idea being that everything else is in the hands of the defense. FIP has its flaws, because it operates on the assumption that a pitcher can't impact balls in play, which means hurlers aren't credited for the majority of their outs, but it can still be a useful tool.
A wide spread between a pitcher's ERA and FIP can suggest bad luck or bad defense that mask some underlying strengths. The Red Sox, interestingly enough, looked a lot better as a staff via FIP than ERA, led by Chris Sale (4.40 ERA vs. 3.39 FIP), David Price (4.28 vs. 3.62), and even Rick Porcello (5.52 vs. 4.76).
Their staff ERA of 4.70 surpassed their 4.28 FIP by the widest margin of any team in baseball. Defensive metrics are notoriously spotty, but Fangraphs ranked Red Sox shortstop Xander Bogaerts dead last at his position in defensive runs saved, saying he cost the Red Sox 19 runs. Similarly, center fielder Jackie Bradley Jr. (minus-2) and third baseman Rafael Devers (minus-13) were considered negatives, too. Bogaerts and Devers aren't going anywhere, but Bradley, a defending Gold Glover, is likely to be traded this winter. The Red Sox could also upgrade their defense at second base.
In any event, we're drifting a little far afield. The point is finding opposing pitchers who significantly underperformed their FIP, which could make them targets this winter. Here are four names to remember.
A first-round pick of the Blue Jays in 2011, Musgrove was traded to the Astros a year later before joining Pittsburgh as the centerpiece in the 2018 Gerrit Cole blockbuster. He made a career-high 31 starts this year, going 11-12 with a 4.44 ERA that masked a 3.82 FIP.
Those relatively middling numbers still established the 26-year-old as Pittsburgh's most effective starter, and he remains under team control through 2022.
With the Pirates in what feels like an eternal rebuild, it's hard to imagine they'd consider any player untouchable. Musgrove could make for an intriguing target.
Gausman is a non-tender candidate, since he's set to make at least $10 million in his final year of arbitration. Chosen fourth overall in the 2012 draft by the Orioles, Gausman was once considered a top-10 prospect.
He has yet to live up to that hype, but he's better than the numbers suggested last year between Atlanta, where he posted a 6.19 ERA (and 4.20 FIP) in 16 starts, and Cincinnati, where he found use as a reliever (4.03 ERA, 3.17 FIP). Gausman struck out a career-high 10 batters per nine innings and is still only 28, so perhaps a flyer is in order, particularly if other teams are viewing him as a reliever and the Red Sox give him an opportunity to start.
How does the AL's loss leader sound? Pitching for a woeful team, Turnbull went just 3-17 with a 4.61 ERA in 30 starts. His 3.99 FIP suggests better stuff than results, however, and he doesn't become a free agent until 2025.
Turnbull throws 95-97 and is considered a piece of Detroit's future, but it never hurts to ask. The 27-year-old went winless in his final 18 starts and is a late bloomer who was still pitching in Double A at age 25.
The rookie went 5-8 with a 5.09 ERA in 21 starts, but his 4.28 FIP and low walk rates (2.2 per nine innings) suggest some promise. The 23-year-old hails from Venezuela and can't become a free agent until 2025. He features a low-90s fastball and changeup, and the Marlins like his competitiveness. Being the Marlins means they're in perpetual fire-sale mode, however, and Lopez is worth a look.
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