What Do The SF Giants Lose By Non-Tendering Tyler Anderson?

The SF Giants non-tendered Tyler Anderson on Wednesday, depleting an already thin starting rotation.

On Wednesday, as MLB teams had to make decisions regarding their arbitration-eligible players, the SF Giants decided to non-tender starting pitcher Tyler Anderson. Given the team’s rotation already had some obvious holes, the decision came as a mild surprise. Anderson was estimated to make around $4 million through arbitration and could be re-signed at a lesser price, but that’s not guaranteed.

It seemed like a rotation without much certainty might be willing to pay a slight premium for continuity. Of course, that depends on how effective Anderson was in 2020. A deeper look at his numbers might explain why the Giants were willing to risk losing him on the open market.

Anderson was drafted by the Colorado Rockies in the first round of the 2011 MLB Draft and was a mainstay in their rotation from 2016-2019. However, a serious injury derailed his 2019 season and led Colorado to designate him for assignment. The Giants front office was willing to bet on the southpaw’s recovery and claimed him off waivers.

In 13 appearances (11 starts) during the pandemic-shortened season, Anderson completed 59.2 innings and posted his best ERA (4.37) and FIP (4.36) since his rookie campaign. However, his peripherals suggested he was far from his peak performances in Colorado.

Anderson struck out just 15.8% of the batters he faced last season. Prior to 2020, he’d never struck out fewer than 20.7% of his opposing batters. At the same time, he walked opposing players at the second-highest rate of his career (9.6%). That is not a recipe for success.

In another concerning trend, Anderson, who has been primarily a ground-ball pitcher over the course of his career, induced grounders at easily the lowest rate of his career. Anderson did allow home runs at the lowest rate of his career, but the percentage of his fly balls that ended up as home runs was at a likely unsustainably low rate (6.1%). His xFIP, which considers home run-to-flyball-rate as something out of a pitcher’s control, estimated his performance equivalent to a career-worst 5.93 ERA. Prior to this year, he’d never recorded an xFIP above 4.80.

Baseball Savant’s expected ERA formula, which uses batted-ball data, gave some constrained praise. Their formula rated Anderson’s performance in line with a 4.77 ERA, far from elite, but a competent back-of-rotation starter. Anderson’s opponent’s exit velocity (77th percentile) and hard-hit rate (85th percentile) both ranked as solidly above-average, and if he fails to regain more strikeout stuff, he’ll need to continue limiting that hard contact to be successful.

It is clearly plausible he could maintain that success. Early in his career, he flashed an elite ability to limit hard contact. Still, the Giants front office has been more inclined to bet on an above-average strikeout and walk rates than anything else. Given the difference between a terrible and elite opponent’s exit velocity is just a couple of miles per hour, it’s easy to see why.

The SF Giants have even less depth in their starting rotation after non-tendering Tyler Anderson. However, Anderson’s quietly solid 2020 season may have been a side-effect of a bit more good luck than it appeared on the surface. While the southpaw would still be a decent depth option for a big-league team in 2021, there are reasons to be concerned about the sustainability of his performance this season.