What did the Astros gain in Kendall Graveman and Rafael Montero?


We’ve all known for a while that the Astros had to address their middling bullpen. The organization itself knew it. This lack of quality depth wasn’t exactly a secret to the world if you took the time to watch the games and review the numbers. On Tuesday afternoon, general manager James Click finally did something about it by trading Abraham Toro and Joe Smith to the Mariners for Kendall Graveman and Rafael Montero. In the middle of a series in Seattle, no less.

To briefly touch upon who Houston traded away, Toro was essentially blocked at the two positions — second and third base — where he could be a regular. Yuli Gurriel is also the first baseman, and we all know who occupies the designated hitter role, so there wasn’t any room for him on this roster outside of insurance and spot duty. The 24-year old now has an opportunity to play every day with the Mariners. The Astros have already felt the impact of this trade — twice by Toro — and before any of their new players have made an appearance.

The other half of the return package was sidearm master Joe Smith. Not much can be said about Smith’s performance other than he was struggling noticeably with a 7.15 ERA in 22 23 innings. There were indications that he was pitching somewhat better than what his ERA indicated, but it still was not great with a 4.36 ERA and 4.08 xFIP. At this point, however, it was clear that the Astros were steering away from giving Smith much in terms of high leverage situations. One must wonder if Smith wasn’t included in a trade whether he would’ve ended up designated for assignment.

For Toro and Smith, the Astros received the services of Kendall Graveman, who possesses a shiny 0.82 ERA in 33 innings this season, and the recently designated for assignment Rafael Montero, who was struggling in his own right this season with a 7.27 ERA in 43 13 innings. On paper, the design of the trade was to add another reliever capable of pitching in high leverage situations to pair with Ryan Pressly, which fits what Graveman has done well this season. On the other hand, Montero has had pitched into some hard times but could represent a worthwhile reclamation project if Houston decides to keep him around.

But the purpose of the trade, first and foremost, was to acquire Graveman. With the 30-year old now in the mix, the Astros have adjusted how they can best deploy their relief corps. It essentially grants manager Dusty Baker additional flexibility, especially as he attempts to bridge the gap between that game’s starter and Pressly. We’ve already seen numerous instances where that bridge was set on fire well before Pressly had a chance to warm up. Also, Graveman brings another dimension out of the bullpen with his sinker/slider combination, which isn’t a typical look for Houston from their current assortment of relievers. Only the recently traded Smith comes to mind as someone who possessed a similar arsenal, although with a much different approach.

What did the Astros gain in Kendall Graveman and Rafael Montero?

Once a struggling starter with generally lackluster results, Graveman’s return to relevance was initiated last season when the Mariners converted him to a full-time reliever. Following two starts and eight earned runs to open his 2020 campaign, the transition to a reliever officially began. The improved results were nearly automatic as the right-hander posted a 3.60 ERA in 10 innings. Eliminate one poor appearance against the Giants on September 17, and Graveman’s ERA as a reliever that season plummets to 0.96. Small sample, yes, but the results were encouraging. As is the case with plenty of former starters turned relievers, the uptick in velocity undoubtedly played a role in his resurgence.

What did the Astros gain in Kendall Graveman and Rafael Montero?

This increase in velocity has carried over into the 2021 season, and Graveman’s numbers have continued to improve when viewed from a macro level. He’s also relied more and more upon his sinker, which is currently 11 runs above average. Only three pitchers have a better run value with their sinkers this season. A 28.1 percent strikeout rate combined with a 6.6 walk rate and a 53.9 percent groundball rate plays well across the board. It is clear why Graveman is an upgrade to this bullpen based on the results alone. If he can maintain a healthy level of control and limit the quality of contact from opposing hitters, he then represents a quality upgrade for a bullpen desperate for one or three.

The results can also blind us to something brewing underneath the surface. There is a reason why I called Graveman’s 0.82 ERA shiny. ERA isn’t a perfect metric as it doesn’t consider the multiple events outside of a pitcher’s control. That is why the inclusion of other data sources — Statcast, for one — has been vital to baseball analysis as we can isolate more what a pitcher controls than what ERA indicates. At first glance, when we see that 0.82 ERA, we already have a bias to believe that figure accurately represents Graveman’s talent level. And while we can only dispute the results so much because results do matter, it is easy not to dig deeper.

In this case, there are indications that the likelihood of Graveman carrying an ERA that low is probably quite low. All of his peripheral numbers paint a pitcher who is still quite good but not at the same level as the 0.82 ERA might lead us to believe.

  • 3.45 xERA
  • 2.88 FIP
  • 3.12 xFIP

By focusing more on what a pitcher can actually control — strikeouts, walks, home runs — we get a better indication of their true level of performance. In the case of xERA, which includes batted ball data like launch angles and exit velocity in its calculation, we gain a more thorough understanding of what a pitcher can control. Based on those figures, it is reasonable to expect some regression for Graveman. As a friendly reminder though, these figures indicate that regression to the mean is possible, even if we aren’t sure entirely when that possibly occurs. There is some evidence of this also occurring with his .176 BABIP, although we need more data to help determine if that figure is his new normal or not. 33 innings for any pitcher isn’t a big enough sample to derive too much value in BABIP other than good defense, and some combination of good fortune is likely involved.

To go even a step further, we can also see how opposing hitters are ever-evolving in their battles against a pitcher. For Graveman, there is some concern that his opponents are starting to adapt to his pitches.

What did the Astros gain in Kendall Graveman and Rafael Montero?

A drop in swinging strike rates tells me that other teams are figuring out Graveman to a certain degree. In turn, we could start watching strikeout rates fall and walk rates rise, which is the general trend emerging from his recent appearances regarding the former.

What did the Astros gain in Kendall Graveman and Rafael Montero?

For a pitcher with a healthy strikeout rate but one far from dominant, that is a troubling trend. In addition, thanks to the crackdown of “sticky stuff” across the league, we’re also seeing spin rates fluctuating in recent weeks. Graveman is no different, and we can already spot a noticeable difference across the board.

What did the Astros gain in Kendall Graveman and Rafael Montero?

Thankfully, his groundball rate has risen in recent appearances, which is helping negate the strikeout drop. I would also be remiss not to note that Graveman did miss some time with a COVID-19 issue. At this point, it is fair to wonder how much that situation has impacted his performance since early June. Well, as long as that sinker performs as well as it has in generating groundballs.

Montero, on the other hand, hasn’t been good. Like, at all. With a 7.27 ERA in 43.1 innings, he was probably included to help offset some of the salary going back to Seattle, namely with Smith. But it is also possible that the Astros see something of value in the 30-year old, who has posted better numbers during his tenure as a reliever with both the Rangers and Mariners before this season.

The potential value that Houston might’ve seen may lie within his overall percentile rankings this season. A change to his pitch repertoire is something to watch here with Montero, especially if he embraces either his four-seam or sinker completely. It is interesting to note that Montero’s groundball rate of 55.2 percent exceeds even Graveman’s rate. As indicated by his 3.73 xERA and 4.03 FIP, better days might be ahead with a change of scenery.

Overall, the Astros added two relievers who can provide value to this roughly average bullpen. The obvious upgrade is Graveman, with Montero as an interesting wild card. Graveman is a free agent at the end of the season, which helps long-term budget-wise. Montero has one more year of arbitration left in 2022. This move, with the inclusion of Smith, keeps the organization below the $210 million threshold for the time being. Let’s see if that remains the same by Friday’s trade deadline.