
Sean Murphy’s incredible first season as a Brave was only slightly marred by xwOBA underperformance and a small swoon in September
The Braves’ big offseason move ahead of the 2023 season was the surprising three-team trade that netted them Sean Murphy. In the same way that pretty much everything came up aces for the Braves over the course of the season, Murphy was a smash hit in his Atlanta debut campaign. In the end, some xwOBA underperformance and a not-so-great September dragged things down, but Murphy is yet another Brave close to the pinnacle of their respective positions.
How Acquired
Murphy was the centerpiece of the Braves’ pre-2023 maneuverings. The team acquired him on December 12, 2022, as part of a three-team deal where the Braves said adios to William Contreras (going to Milwaukee), Royber Salinas, Kyle Muller, Manny Pina, and Freddy Tarnok (headed to Oakland).
Prior to that point, Murphy had been a lifetime Athletic, the veteran of four major league seasons, after being drafted by Oakland in the third round of the 2016 MLB Draft.
When the Braves acquired him, Murphy was arbitration-eligible for the first time in his career. But, things never got that far, as just 15 days after the trade, the team announced that they had inked Murphy to $73 million extension covering the next six seasons, including an additional $15 million club option with no buyout for the 2029 season.
What were the expectations?
Murphy posted a 5.0 fWAR season in 2022 with a very-rare-for-a-catcher 612 PAs. Offensively, he had a career 116 wRC+ coming into 2023, with a 122 mark in 2022, putting him squarely in the top tier of catcher offensive. He was also in the top tier of catcher defensive performance. Pretty much the only reason why Murphy was not necessarily expected to be the best catcher in baseball in 2023 was because guys like J.T. Realmuto and Adley Rutschman were primed to add value with their legs in a way that just isn’t in Murphy’s wheelhouse.
In any case, Murphy’s projections were generally around 3-4 WAR in around 400 PAs (a much more frequent total for a catcher in a given season), essentially All-Star-level production.
2023 Results
Those projection point estimates were pretty much exactly where Murphy ended up, albeit in a somewhat-weird way. Murphy’s top-line results were 438 PAs, a 129 wRC+, and well above average framing value, giving him 4.2 fWAR, and an fWAR/600 pace of over 5.7. He finished fifth among catchers in fWAR, but with the best per-PA rate among anyone with more than 50 PAs except Bo Naylor, who himself only got 230 PAs and outhit his xwOBA by a bunch.
Defensively, Murphy finished well above average in all aspects of his position, including the best Statcast blocking numbers out of anyone. He wasn’t among the elite framers in 2023, but he was closer to them than to league-average framer types.
All of this impressive production also came with the giant caveat that Murphy actually massively underhit his xwOBA, by right around .030. Among the 362 players that finished 2023 with 200 or more PAs, Murphy was 11th in xwOBA (.395), but he was 30th in wOBA (.366). That ranked as one of the 20 or so largest underperformances among this group, joining teammates Ronald Acuña Jr. and Travis d’Arnaud.
I suppose it’s also worth noting here that Murphy’s playing time on the path to getting his 438 PAs was kind of strange, considering his level of production. He played roughly three out of four games for the team in April and May, though this was driven largely by d’Arnaud’s concussion woes early on. After that, it was largely a 50-50 split with d’Arnaud, as a few dings and dangs evened out the times through the summer that Murphy tended to start two out of three games.
What went right?
Realistically, it’s hard to have asked for much more out of Murphy in 2023, aside from just playing more often. Among the players that bested him in xwOBA, three were outfielders, four were designated hitters, and then you had a first baseman, Corey Seager, and Mookie Betts’ varied adventures. That Murphy was able to post a near-.400 xwOBA while also donning the tools of ignorance at the same time, well, that kind of blows my mind, and it should blow yours, too.
It probably goes without saying at this point that the Braves probably knew what they were getting themselves into when acquiring Murphy, which is why they made the trade for him and not for a different player. Prior to trade, and especially in 2022, Murphy showcased prodigious raw power, but took the edge off his potential by prioritizing contact and, at times (but not always nor consistently!) being fairly injudicious with his swings, offering at things he could hit rather than hit really hard. Well, the Braves got the buy-in they needed to turn him into a batting monster in a hurry.
Murphy posted a barrel rate of nearly 22 percent in April (league average is around seven percent!). How did he do that? Well, in brief, he just kind of stopped offering at things he couldn’t barrel. April 2023 featured the lowest calendar month chase rate of his career going back to the start of 2021, as well as a relatively low z-swing rate and, as expected, an elevated z-whiff rate. It was like he was a Brave all along, except he wasn’t.
These things didn’t keep up all season — for example, his barrel rate largely dwindled from its lofty highs as the season wound on, his z-swing rate bounced up, his z-whiff plummeted late, and so on. But there was clearly a rapid approach change, and it paid huge dividends.
The most epic Murphy moment of the season, then, came quite fittingly in April. The Braves blew a two-run lead to the Reds in the ninth, and then fell behind again in the tenth. Murphy literally ended the game with one pitch, as he took the first pitch the Braves received in extra innings and turned it into a walkoff homer:
In fact, that whole game was an awesome one for Murphy, as he had a leadoff double in the fourth in a scoreless tie (didn’t score), and then broke the scoreless tie with an RBI double in the sixth, while adding two deep-count strikeouts.
What went wrong?
For one, the xwOBA underperformance. But, for another, a lot of people are going to focus on his late-season slide, even though looking at outputs really exaggerates what happened.
Murphy did have a dreadful September in terms of results, with a 36 wRC+. But, his xwOBA was a fine .328 that month. Sure, it was way lower than in any other month (his other worst was a .344 in July), but what was really brutal was that he underperformed his xwOBA by .100 in September, hence the terrible outputs.
There’s some vortex of stuff to discuss going on with regards to both his decline in performance late in the year and his overall usage by the Braves over the course of the season. Remember that Murphy played a lot more in April and May than afterwards. He also posted his two best xwOBAs in those months. But, he also cleared a .400 xwOBA in August, when he had a net three starts over d’Arnaud. Basically, while it might be tempting to say that either starting too much or starting not enough dragged down his performance, I’m not sure you can actually build a compelling case for either. Instead, he had a relatively bad month at the end of the season; it happens.
One miserable game stands out for the catcher: July 15, against the White Sox. Sometimes, the universe just has it out for you. In this game, Murphy: struck out against Lance Lynn; flew out weakly with two on and two out in a tie game; had a first-pitch lineout down by one; struck out after a leadoff double down by two; and the coup de grace:
Someone that doesn’t run like Murphy probably ties the game on that broken-bat grounder, but alas.
Murphy also didn’t do much in the postseason, with a couple of singles in seven PAs, but the fact that he only got seven PAs in four games goes back to the usage stuff from earlier.
2024 Outlook
Murphy’s projections are interesting at first glance, with Steamer forecasting a big fall-off for a point estimate given what he managed in 2023. Steamer has him at a 114 wRC+ next year, which seems odd to me given his xwOBA. The 3.2 WAR in 400-odd PAs as a central estimate for his 2024 production would’ve made more sense to me before his 2023 season, but we’ll see. ZiPS has Murphy closer to 5 WAR, but also closer to 500 PAs; it remains to be seen whether he’ll actually get that much playing time with d’Arnaud still around.
In any case, Murphy is another locked-down piece of this impressive Braves core (and corps), and given what we saw from him in 2023, he’ll probably give his team best-in-class production at catcher, or something close to it, once again.