Jazz Chisholm Jr. has openly described his current season as "sucks," citing a surprising nosedive in his performance, especially against fastballs. As of Wednesday, Chisholm's batting average stood at .217, a 25-point drop from the previous year, with his on-base plus slugging (OPS) declining by 121 points to .692.
Chisholm, who has historically excelled against fastballs, is now struggling significantly with four-seam fastballs. Last season, he posted a .548 slugging percentage against this pitch type. This year, his performance against four-seamers has plummeted, with his Run Value of minus-11 ranking as the third-worst among major league players against that specific pitch. He entered play hitting .187 with a .309 slugging percentage against four-seamers.
"I don’t know," Chisholm said when asked about the cause of his struggles. "It’s a good question."
Opposing pitchers have taken notice and adjusted their approach. In May, Chisholm saw 46.5 percent fastballs, a figure that has steadily increased in subsequent months. Entering August, he was facing a consistent diet of 58.9 percent fastballs.
In response, Chisholm has attempted to be more aggressive on early pitches. From Opening Day through the end of June, he swung at 24.3 percent of first-pitch fastballs. Since July began, however, knowing that fastballs are likely coming due to his struggles, he has swung at 49.3 percent of them, collecting two singles in seven at-bats.
These difficulties come during a contract year where Chisholm had envisioned a season of 50 home runs and 50 steals. He currently has 17 home runs and 31 steals, and has reportedly lost the trust of manager Aaron Boone against left-handed pitchers. His struggles extend to other areas of his game, including baserunning issues, such as being picked off, and tying for the American League lead among second basemen with eight errors. He has also played through numerous minor injuries.
Chisholm believes there are subtle changes in four-seam fastballs, stating, "I just feel like there’s a lot of different four-seamers nowadays. A four-seamer isn’t as normal as it used to be."
Contributing factors may include a slight dip in bat speed, from an average of 73.9 mph last year to 73.2 mph this season. His hitting coach, James Rowson, suggested that timing is the primary issue, leading to Chisholm being either late on fastballs or too early on off-speed pitches. Despite the challenges, Chisholm is actively working on improving his performance against fastballs in the second half of the season.
