Some Astros off season thoughts: Valdez and back up catcher

[I am on vacation this week, but I put this article in the can so you would have something to read.]

The Astros are in off-season mode, which means they will be working on constructing next year’s team. It’s a little early for me to formulate my opinions on Astros’ moves related to team construction. Also until we know who the manager will be, we don’t know who will be the hitting and pitching coaches, and that’s a critical input to the off-season moves.

But I peeled off two discrete questions which are related to the Astros off-season. The first question doesn’t directly involve any off-season moves. Framber Valdez will be 30 years old next season. What does that mean for his future pitching trajectory? What is the liklihood of improvement vs. decline? That should be major consideration for the Astros if they are considering a long term contract extension offer. Also, the answer to this question affects how the Astros should approach the type of starting pitcher, if any, they should acquire this off-season.

The second question pertains to how the Astros will address their backup catcher position next year. Dana Brown has already stated that he expects Yainer Diaz to open as the primary catcher, but adds that the team will have to address the back up catcher position.

Framber Valdez

Framber Valdez is the Co-Ace of the Astros’ starting pitching staff. He had a reasonably good regular season in 2023 (3.45 ERA), which is comprised of a very good first half of the season (2.51 ERA) and a significantly worse second half (4.68 ERA). Some of the issues in the second half continued into the playoffs. Perhaps the second half and playoffs reflect the large workload Valdez experienced in 2022 and prior to spring training.

In an effort to predict the liklihood that Valdez can significantly improve his results in 2024, perhaps we should contemplate the impact of aging on future results. Valdez will be 30 years old at the start of next season. Other than the really old man of the pitching staff, Justin Verlander, Valdez is the oldest Astros’ starting pitcher.

A number of articles have studied the impact of aging on pitching performance (see for example this Fangraphs article), particularly as the pitcher reaches age 30. Basically, pitchers who reach age 30 tend to decline gradually in subsequent years, with starting pitchers suffering the slowest effect and relievers a faster decline. This probably reflects the connection between aging and fastball velocity, which affects relievers more than starters. Starting pitchers can offset declining velocity with improved breaking or off-speed pitches. However, strike out and walk rates may gradually increase.

In order to develop a rudimentary notion of the possible impact of aging on Valdez’s performance over the next three season, I examined the career trajectories of the eight most similar pitchers through age 29, based on Baseball-Reference’s similarity scores for Framber Valdez. The pitchers are: Jim Deshaies, Teddy Higuera, Alex Wood, James Paxton, Harvey Haddix, Yu Darvish, Eric Show, and Alex Cobb. (I didn’t include Lance Lynn, who was out for a full season at age 29.)

I examined ERA+ (percent better or worse than average), FIP, and WHIP for age 29 compared to the age 30 - 32 average. Here is the average percent change in those stats in the three years after age 29:

ERA+ -6.4% FIP +6.11% WHIP +1.4%

This comparison would suggest that Framber Valdez’s ERA would increase from 3.45 to 3.90 during the next three years. Similarly the FIP would increase from 3.50 to 3.71, and the WHIP would increase from 1.12 to 1.14. But averages can be misleading because they don’t show the variance in the data. Two of the eight similar pitchers actually improved their performance over the three years at age 30 - 32. Among the remaining six pitchers who declined, two exceeded 20% worse ERA+ and three exceeded 20% higher FIP.

One can certainly question whether these results have much predictive power. For one thing, Baseball-Reference’s older methodology for computing player similarity scores is subject to criticism, and there may be better algorithms for computing comparable players. But I think my comparison serves the purpose of confirming that aging is a factor which may offset possible improvements in performance.

Framber Valdez will be under team control in 2024 - 2025, unless the Astros sign an extension contract beyond those remaining two years. However, as he pitches into his 30’s, it’s possible that he will produce results more like a mid-rotation starter than an ace starter. Has he reached the peak of his value? We don’t know, because we aren’t oracles. But it’s possible.

Back Up Catcher

The Astros expect Yainer Diaz to be the primary catcher next year. But the Astros will likely be in the market for acquiring a back up catcher for next season. My preliminary review of the catcher free agent market? Uninspiring is my immedate impression.

The better candidates as ranked by WAR:

1. Mitch Garver, who shares catching duties with the Rangers, is probably the best catcher on the FA market. He combines exceptional power (19 HR in 344 PA) and a solid offensive profile (wRC+ 138) with average-ish defense. He has thrown out 22% of SB attempts which is not great, but OK. His framing and DRS are around average. While I certainly would be pleased if the Astros acquired him as a back up, I doubt it happens. For one thing, he is likely to get paid well. Christian Vazquez signed a 3 X $30 M contract with Minnesota last year, and Garver profiles as a more productive catcher. He hit 3 HR and accumulated 14 RBI in the playoffs, which likely makes him more attractive to the market, and probably drives his price tag higher. Given the Astros’ payroll situation, I doubt that they intend on paying a lot for a back up catcher.
2. Gary Sanchez, who came on strong after joining the Padres, improved on almost all facets of his game in 2023. He may go from a catcher who had difficulty signing a contract in 2023 to one of the better catchers on the market in 2024. Sanchez hit 19 HRs and has 111 wRC+ in 267 PA. Sanchez seemed to rebound from his poor defensive reputation, putting up +7 defensive runs saved and pretty much average framing numbers. It’s hard to say how much he will cost. But his seasons previous to 2023 may suppress his price tag.
3. Victor Caratini, the switch hitting Brewers back up catcher, is slightly below average on offense (wRC+ 94), but that means he is better than the typical catcher. He isn’t particularly good at throwing out runners (13% CS rate), but his framing numbers are exceptional, and his other defensive skills are not bad. He might be a reasonable candidate for the Astros’ budget and needs.
4. Seattle catcher Tom Murphy was impressive on offense in 2023, with a 140 wRC+ and 8 HR in 140 PA. Defense—that’s another story. He had 1 caught stealing in 28 attempts. He is negative on both framing and DRS. Whether the Astros would be interesting may depend on whether they want offense or defense out of the back up catcher. He seems unlikely, given the defensive profile.
5. Austin Hedges was acquired by the Rangers from the Pirates when Jonah Heim was injured. He is the opposite of Murphy—good defense and very weak offense. He was not good at throwing out runners, but his defense was good enough for +11 defensive runs saved and an outstanding framing of +16.9 runs. However, his offense probably is worse than Maldonado’s. Again, it may depend on how much the Astros value defense in the back up catcher, but I could see the Astros showing interest in Hedges.
6. Yasmani Grandal is the 34 year old White Sox catcher. At one time, Grandal was one of the best offensive catchers in baseball. His offense is below average now (wRC+80) but still within the range common for the position. Also, his prior reputation supported outstanding defensive and framing skills which were among the best in baseball, but if you believe the metrics, his defense has fallen off some. He might be good at providing the veteran presence that teams seek in a back up catcher role. (Think of the role Brian McCann played for the Astros in 2017.) However, he would have to take a pay cut to sign as a back up catcher (his current AAV is $18 M.) and I doubt that happens.

The rest of the free agent list has a lot of candidates with very poor offense and sometime poor defense to supplement it. If the Astros are going to fish for free agents from this remaining group, the Astros may be better off trying to retain Maldonado to serve as the back up catcher. That assumes Maldy is willing to accept the lesser role, but there could be some benefit if he does, given his knowledge of the Astros’ pitchers and his leadership role in the Astros’ clubhouse. So long as Maldy’s playing time is consistent with back up duty, there probably isn’t a big problem if he is assigned to catch a couple of the starting pitchers. Any back up catcher who is acquired would likely have a similar assignment.