How Much Better Is the Phillies’ Bullpen Post-Deadline?

The Philadelphia Phillies didn’t make a huge splash at the trade deadline. They didn’t have to. This team has not been playing its best baseball as of late, but they’re still in a strong position to make the postseason (FanGraphs playoff odds 99.3%), and simply put, there aren’t a lot of holes on the roster.

So, much like the Phillies have done at each of the past three deadlines under Dave Dombrowski’s stewardship, they made a handful of smaller trades to improve at the margins.

One of those moves was acquiring Austin Hays from the Orioles, checking a righty-batting fourth outfielder off the deadline shopping list.

The other two additions the Phillies made were bullpen arms: right-hander Carlos Estévez and left-hander Tanner Banks.

They sent pitching prospects George Klassen and Samuel Aldegheri to the Angels in exchange for Estévez, and infield prospect William Bergolla to the White Sox in exchange for Banks.

To make room for Hays, Estévez, and Banks, the Phillies also parted ways with an outfielder and two relievers: Cristian Pache (OF), Seranthony Domínguez (RHP), and Gregory Soto (LHP).

Pache and Domínguez went to the Orioles in the Hays trade, while Soto joined them a few days later in exchange for pitching prospects Seth Johnson and Moises Chace.

Hays (101 wRC+) is a pretty clear upgrade over Pache (65 wRC+) as a right-handed bench outfielder. Hays has far superior offensive numbers, this season and throughout his career.

But what about the bullpen? How much better is the Phillies’ arm barn after swapping out Domínguez and Soto for Estévez and Banks?

Let’s take a closer look.

How Much Better Is the Phillies’ Bullpen With Estévez and Banks?

The simplest way to contrast the Phillies’ bullpen from before and after the trade deadline is to compare the two right-handers (Estévez and Domínguez) and the two southpaws (Banks and Soto).

It’s not as if one will simply take over the other’s workload (especially in the case of Estévez and Domínguez), but at the end of the day, if Estévez is better than Domínguez and Banks is better than Soto, the Phillies’ bullpen will be better off.

Estévez and Domínguez

Estévez is an All-Star closer. Domínguez has been frustrating Phillies fans all year. Easy upgrade, right?

Well, maybe. But these two pitchers are actually a whole lot closer in talent than their 2024 ERAs might suggest:

2024 Stats

Estévez has significantly improved his control this season, and he’s issuing far fewer walks than Domínguez. However, Domínguez has done a much better job limiting hard contact. He has also been better at inducing groundballs, while Estévez has been far more likely to give up hard-hit balls.

Ultimately, the biggest difference between their seasons boils down to factors largely outside their control. Estévez is thriving thanks to an unsustainably low BABIP and HR/FB ratio. That explains why his xERA, xFIP, and SIERA are quite close to Domínguez’s figures, despite the wide gap between their ERAs.

To be clear, Estévez is still enjoying a better season than Domínguez, especially because he has worked in higher leverage spots. However, the difference between them is one of inches, not miles. That’s easier to see when you look at their stats over a larger sample size:

2022-24 Stats

The pitch modeling systems PitchingBot and Stuff+ suggest Domínguez has much nastier stuff, but Estévez has far better command. All told, both systems see the two pitchers as (pretty much) equals. Estévez has a 3.95 botERA and 104 Pitching+ this year, while Domínguez has a 4.02 botERA and a 102 Pitching+.

Domínguez has flashed phenomenal stuff over his tenure with the Phillies, but he has struggled to put it all together for a prolonged period of time.

Thus, I’d argue that Domínguez has more upside than Estévez, but Estévez is more consistent and reliable. Considering the fact that Estévez is also in the middle of a better season, it’s not hard to see why the Phillies made the choice that they did. That said, we’re probably talking about a marginal upgrade at best.

Finally, manager Rob Thomson’s usage of Estévez is another factor worth considering. Estévez comes with a closer’s pedigree, and Thomson has already suggested he plans to use him in a ninth-inning role.

If Thomson starts using Estévez in the highest-leverage spots – those that should go to better arms like Jeff Hoffman and Matt Strahm – then Estévez’s addition to the bullpen could almost cause more harm than good.

Banks and Soto

Banks will be more of a direct replacement for Soto, since he should slot in as the third left-hander in Philadelphia’s bullpen.

In this case, Soto is the bigger name with a longer track record in the majors, but with the way these two have pitched this season (to say nothing of reported clubhouse issues), it’s easy to see why the Phillies opted to pursue Banks:

It’s hard to find a single statistical category in which Soto has a meaningful advantage. The two have similar strikeout rates, but Banks has done a much better job keeping his walks in check.

Similarly, both pitchers have done a good job inducing groundballs, but Banks has done better work to limit hard contact.

Finally, while Soto and Banks have similar ERAs, Banks has been the better pitcher according to every major ERA estimator, including xERA, FIP, xFIP, and SIERA. Moreover, he also has a higher average leverage index when entering games.

In addition, Banks is under team control through the 2028 season, while Soto will be a free agent after 2025. That’s not particularly important for a team trying to compete right now, but it’s still worth mentioning.

The only drawback when it comes to Banks is his limited MLB experience. It’s fair to wonder how long he can maintain this level of performance. He made his MLB debut in 2022 at 30 years old, and he has taken a big step forward this year in his age-32 campaign.

As good as Banks has looked, 49.0 innings this year is a small sample size. Nevertheless, the Phillies clearly think his stuff is for real, and perhaps they have a plan to further improve his impressive five-pitch arsenal. (A little more Caleb Cotham magic, anyone?)

Why Did the Phillies Trade Domínguez and Soto?

So, we’ve compared the relievers the Phillies added to the ones they lost. But there’s another question we still need to address: Why did they have to give up Domínguez and Soto at all?

The Phillies needed to make room for Estévez and Banks in the bullpen. Yet, wouldn’t they have been better off replacing Yunior Marte and José Ruiz instead?

Yunior Marte and José Ruiz

Marte has a 4.64 ERA and a 4.52 FIP in 21.1 IP this year. His 4.13 SIERA is a little more promising, but his 6.09 xERA tells us he has been allowing way too much hard contact.

In his latest stint with the big league club (he has been optioned and recalled a couple of times already), Marte has allowed five earned runs on seven hits and four walks in five innings of work.

The 29-year-old owns a career 5.13 ERA and 4.52 FIP across 108.2 innings of mostly low-leverage work.

Ruiz, also 29, has a 4.50 ERA and a matching 4.50 xERA in 32.0 IP this season. Some of his underlying numbers are a little better (especially his 3.43 SIERA), but his MLB track record is not. He has a career 4.51 ERA in 251.1 IP. Over the last three seasons, he has a 4.99 ERA in 133 games.

The veteran right-hander has not been any better recently. Ruiz has a 6.00 ERA and 5.16 FIP since the start of June, and an 8.00 ERA and 8.16 FIP since the start of July.

I don’t mean to rag on Marte and Ruiz. Both have been perfectly serviceable inning eaters at the bottom of Philadelphia’s bullpen.

However, there is little doubt the Phillies would rather have Domínguez or Soto on the mound with a big game on the line.

So, why are Marte and Ruiz still pitching in red pinstripes, while Domínguez and Soto are suiting up for the Orioles instead?

Eye On the Playoffs

For one thing, it’s critical to remember that the relievers at the very bottom of the bullpen depth chart usually don’t get much work in the postseason.

The Phillies are already in a strong position to make the playoffs, so they don’t need to worry too much about their bullpen for the rest of the regular season. Once they get to October, they will rely on Hoffman, Strahm, José Alvarado, and Orion Kerkering – and, of course, Estévez and Banks.

In addition, the Phillies are surely hoping Spencer Turnbull will return from the IL and rejoin the bullpen down the stretch. They might also make room for Tyler Phillips in the postseason ‘pen, considering how well he has pitched (1.80 ERA, 3.11 xERA) across 25 innings so far this year.

The Phillies would be better off in the postseason if they still had Domínguez and Soto on the roster, but only slightly, marginally so.

Thus, Dombrowski used Domínguez as a trade chip, so he didn’t have to part with any prospects to land Hays. Then, he flipped Soto to replenish some of the young pitching talent he gave up in the deal for Estévez.

The 2024 season (and postseason) was Dombrowski’s top priority at the deadline. There’s no question about that. Yet, he also made some shrewd moves with the future in mind. That’s just smart baseball business.

The Philadelphia Phillies didn’t make a huge splash at the trade deadline. But they didn’t have to.

The Phillies’ bullpen and offense are slightly better than they were last week. For a 65-43 Philadelphia Phillies team with a 6.5-game lead in the NL East, that should be more than enough.