Welcome to our 2020 Red Sox in Review series. This is, as you can probably guess, where we will be reviewing all of the players who made at least a modest impact on the Red Sox in 2020. Every week day we’ll be deep diving into one player. For each edition we’ll describe the season in a sentence, look at the positives from the year as well as negatives, look back at our one big question from the season preview and look ahead to the 2021 season. We’ll be going in alphabetical order of the players on this list. You can look over that list and drop a name in the comments if you think I left anyone out who should be mentioned here. Got it? Good. Today we are exploring how 2020 was for Tanner Houck.
2020 in one sentence
Tanner Houck was only called up from the Alternate Site in time to make three starts, but he made the most of his opportunity and provided an incredibly rare sense of optimism on the Red Sox pitching staff.
Even for those who were relatively optimistic about what Houck could provide this season had to be surprised by just how effective his first few major-league starts were. The righty and former first round pick made three starts in total with 17 innings of work, and in that time he allowed just two runs, only one of which was earned, to go with 21 strikeouts and nine walks. Yes it’s a small sample and yes there is still a long way to go for him to be a consistent starter at this level, but it’s also worth noting that all three outings came against postseason teams in the Marlins, Yankees and Braves. We have all winter (and a section later on here) to talk about the issues with the sample here and to warn against too much optimism, but at the end of the day Houck passed every test thrown at him. That’s all we can ask for.
The most impressive part of these performances, to me at least, didn’t even have anything to do with a statistical anomaly or anything like that. It was simply his poise. Houck didn’t look like a rookie who was thrust into major-league action for the first time in the midst of a pandemic in an empty ballpark after not pitching in organized games for almost a year. This was not an easy situation. Even in normal situations, it’s normal for rookie pitchers to let things snowball when they start to go wrong. That never happened with Houck. He wasn’t perfect and batters did reach base, but the rookie was even better in these situations, most impressively nearly doubling his ground ball rate from 39 percent with the bases empty to 67 percent with runners on. Even with the things he still has to work on, Houck at least had the temperament for these moments.
Let’s not take anything away from the pure talent, though, because that is also present here. One of the things we had known about Houck before he even got to the majors was that, when things were going well, he could get whiffs. That’s exactly what happened in this initial run through the majors. In total, the righty struck out an even third of the batters he faced. Most of that success came to success on getting batters to swing through pitches out of the zone, as he actually had a swinging strike rate that was worse than average on pitches in the zone. He’ll have to improve that in a larger sample to keep such a strong strikeout rate, but he also has quite a ways to drop while still staying effective. The league-average rate for starters in 2020, for what it’s worth, was 23 percent.
If we’re looking at the pitch mix, it was clear from the get-go that Houck’s slider would steal the day, and the numbers unsurprisingly reflected that. While his fastballs were effective as well, the slider was incredible. He threw the breaking ball, which has drawn some loose comparisons to Chris Sale’s offering from the other side of the mound, 35 percent of the time. According to Baseball Savant, batters put up a wOBA (on the same scale as OBP) of .115 against the pitch, which is ridiculous, and the expected wOBA (based on batted ball and plate discipline data) wasn’t much higher at .182. Throw in a whiff rate on the pitch approaching 50 percent, and baby you got a stew goin’.
For as impressive as this first taste of the majors was, however, there are still some things with Houck that cause some hesitation in projecting him moving forward. To me, the number one issue and the number one thing to watch for in 2021 was/is his usage (or lack thereof) of his offspeed pitch. In the past he threw a changeup, but scrapped that recently to try and use a splitter instead. He needs one of those to work because in the past, his other three offerings — the aforementioned slider along with both a four-seam and a two-seam fastballs — have been susceptible to being hit by lefties. He doesn’t get a failing grade on his offspeed pitches, though. Instead, it’s an incomplete. Houck threw only eight splitters combined across his three starts.
It worked here, of course, but as teams see him more he’ll almost certainly have to find more confidence in one of these offerings — the splitter is more likely — so that he can at least throw it 10-15 percent of the time, almost solely against lefties. There is some reason for mild optimism on this front, though. For one thing, the splitter was just added to the repertoire so the lack of confidence is understandable. It’s not at all unreasonable to think Houck will be more willing to work in the pitch after a full winter of working on it. I would also mention that he started to throw the slider more effectively against lefties, throwing it more towards the back foot (a la Sale) more often. It’s easier said than done to hit that spot consistently with positive results, but if he can then the offspeed pitch becomes less important.
Houck also walked far too many batters, with a final rate coming in at 14 percent. The good news is he didn’t let that hurt him too much in these three starts. As I mentioned above, he got a bunch of ground balls once he put runners on base, which led to huge double plays. Some of that was certainly on purpose, going more to his sinker in that situation, but some of it will also even out a bit over a larger sample. He’s never going to have a low walk rate as he leans heavily on sliders and sinkers that are most effective out of the zone, but if he can’t get that rate down to nine or ten percent, things could get dicey in larger samples.
The Big Question
Looking ahead to 2021
What the Red Sox decide to do with Houck at the start of next season is one of the most interesting storylines of the offseason. On the one hand, he performed well enough that it’s not crazy to give him a starting job right off the bat. On the other hand, there are still things to work on and starting with more depth is better than not. My expectation is that he’s part of a group of three or four, along with Nick Pivetta and a minor-league signing or two, competing for the fifth rotation spot. There’s no doubt he’ll be up at 2021 at some point, but how long he’s there and whether it’s only in the rotation is totally up in the air at this point.