Patience Is a Virtue for O’s Mountcastle

Last season was a fun one for the Baltimore Orioles. Coming off of five straight sub-.500 seasons and a particularly torturous 110-loss campaign, the Birds had a 24-35 record before starting to turn things around in late June. Just before the All-Star break, they went on an improbable 10-game winning streak to jump over .500, and after the break, they kept the momentum moving their way, even making a short-lived run at the third American League Wild Card spot (they ultimately fell just three games short). It started to look like the dawn of a new era in Baltimore, and much of the spark came from a revamped lineup. Adley Rutschman and Gunnar Henderson made their highly anticipated big league debuts and did not disappoint – particularly the former, who turned in one of the finest rookie seasons by a catcher in recent memory. Cedric Mullins followed up his breakout 2021 with another solid season. Anthony Santander set a new career high with a team-leading 33 home runs. And then there was Ryan Mountcastle.

After leading the Orioles with 33 homers and 89 RBI in 2021 in his full-season debut, Mountcastle’s offensive production faded last season. He hit just 22 home runs, while his slugging dropped from .487 to .423, his wOBA from .335 to .316, and his wRC+ from 111 to 106. His defense improved enough to allow him to reach 1.6 WAR, a new career high, but for a player whose calling card is power, his waning surface-level thump was at least indicative of a sophomore slump and at most a cause for concern.

But Mountcastle’s Statcast profile and expected stats tell an entirely different story. In 2021, the slugger was in the middle of the pack, with an average exit velocity of 89.1 mph (45th percentile) and a 39.7% hard-hit rate (41st); his .245 xBA and .326 xwOBA placed him in the 36th and 47th percentiles, respectively. By these measures, his 2022 was one of the better year-over-year improvements in baseball. He added 2.2 mph to his average exit velocity, the seventh-largest increase among players who qualified in both years, and 6.6 percentage points to his hard-hit rate, the sixth-most in that group. Just four hitters added more to their xBAs than his .032 points, and the only hitters who managed to improve their xwOBAs more than his .036-point jump were Yordan Alvarez (.073), Christian Walker (.048), and Aaron Judge (.045). His was one of just 40 player-seasons in the Statcast era with 60-plus barrels.

To go further, from his batted ball profile, he would have been expected to be among the best hitters in baseball – his xBA, xSLG, and xwOBA were all above the 90th percentile. Instead, his wOBA was in just the 33rd percentile – 87th among 130 qualified hitters. No hitter had a greater negative gap between his wOBA and xwOBA than Mountcastle’s .046:

A couple of factors outside of Mountcastle’s control were working against him in 2022. First, prior to the season, the Orioles decided to alter the dimensions of Oriole Park, moving the left field wall back 26.5 feet and raising it about six feet in an effort to make the park more neutral. This was likely unpopular with their preeminent right-handed slugger – just like that, the venue’s Statcast home run park factor went from the highest in baseball in 2021 at 153 to the sixth-lowest at 77. Here’s Mountcastle’s 2022 spray chart at home, overlaid onto the new OPACY dimensions:

There’s a good handful of very close misses there, some of which were hit right in the section formerly home to bleacher seats and some of which seem to constitute bad luck. That brings us to the other factor that was out of Mountcastle’s control – thanks (or no thanks) to more changes in the ball, fly balls died shorter in 2022 than in years prior. The league HR/FB rate was its lowest since 2015, and hitters were rewarded less than ever before in the Statcast era for barreling the ball up. The league-wide .728 average, 2.410 slugging, and 1.289 wOBA on barrels were all the lowest in that time. Even still, Mountcastle’s .623 average, 1.967 slugging, and 1.078 wOBA on his 61 barrels were all significantly lower than league average. His 22 home runs were the fewest by a player with 60-plus barrels in the Statcast era.

Between the new park dimensions, a new ball, and some amount of bad luck, it was a frustrating year for Mountcastle, who sure seemed to find a lot of gloves on balls that seemed destined for the stands off the bat.

Unfortunately, much of this will remain out of his hands in 2023, but Mountcastle’s batted ball profile was strong enough that if he repeats it in the coming year, he has a good chance to take some serious strides forward. In 2022, six hitters placed in the top 15% in the league in xBA, xSLG, xwOBA, barrel rate, and average exit velocity: Alvarez, Judge, Bryce Harper, Shohei Ohtani, Austin Riley, and Mountcastle:

One thing Mountcastle does have control over is the biggest hole in his offensive approach: his lack of patience. In his two full seasons, he’s yet to place better than the 37th percentile in BB%, the 24th in K%, the 18th in Whiff%, and the eighth in chase rate. He swings big and he swings often. As he continues to make hard contact on pitches in the zone – his 93.8 mph average exit velocity on strikes was 3.5 mph above league average – pitchers will continue to exploit his propensity for swinging at bad pitches.

In 2022, they did that most effectively with offspeed pitches, particularly low and fading to the pitcher’s arm side. Take a look at this group of offspeed offerings that came in around the shadow of the plate, but not in the strike zone. Mountcastle swung at 71.1% of these, managing just one single on 32 swings:

There’s good news, though – Mountcastle’s approach improved steadily over the back half of 2022, and the 30-game rolling averages for his O-Swing% and SwStr% were at their lowest in the last few games of the regular season. He chased less of every pitch type, reaching career-low rates against fastballs (27.2%) and breaking balls (23.2%) in the month of September. This helped him turn his season around after a rough July and early August, and it bodes well going into 2023. If he is able to limit giving away free strikes when he doesn’t have to, he’ll be a really tough out:

Despite the above, our various projection models don’t seem to anticipate Mountcastle taking too large of a next step. With pretty strong consensus, the models expect his walk rate to linger just above 7.0%, his strikeout rate to stick around 25.0%, and his slash line to end up somewhere in the range of .255/.315/.445, a modest improvement – mostly in slugging – over last year. It’s a reasonable suggestion for a player whose two full seasons haven’t wavered all too far from those figures, but given his success getting the bat to the ball, Mountcastle seems to have a decent shot to move up a tier.

It feels strange to talk about a player with 55 big league home runs in the last two years as a breakout candidate. But Mountcastle is still looking for a season where it all comes together, and 2023 could be that year. At this point, a change of luck on hard contact and a little more patience at the plate seem to be all he needs to turn into the type of hitter who could really improve the Orioles lineup. As the Birds look forward to Rutschman and Henderson’s first full seasons in the majors, their lineup is starting to really fill out with young talent. A Mountcastle breakout could be a huge boon to a club looking to keep the momentum moving their way.