The Arizona Diamondbacks entered the final weekend before the All-Star break hoping to finish the first half on a positive note, but another injury to their starting rotation quickly shifted the focus away from the field. Veteran right-hander Zac Gallen was removed from his scheduled start against the Los Angeles Dodgers after experiencing inflammation in his right elbow.
The development adds to an increasingly difficult stretch for Arizona’s pitching staff, which has already been forced to overcome several injuries throughout the season. Although Gallen has struggled statistically in 2026, he remained one of the club’s most dependable starters in terms of durability and workload.
Manager Torey Lovullo confirmed that Gallen returned to Arizona to undergo medical imaging and is expected to be placed on the 15-day injured list. In response, the Diamondbacks promoted rookie left-hander Mitch Bratt from Triple-A Reno to make the start in the series finale before the All-Star break.
The timing could hardly be worse for Arizona. With multiple key starters already unavailable, the Diamondbacks are now relying heavily on inexperienced pitchers as they attempt to remain competitive during the second half of the season.
1. Gallen’s Difficult Season Takes Another Turn
Although Gallen entered the season expected to lead Arizona’s rotation, 2026 has proven to be one of the most challenging campaigns of his major league career. Before the injury, the 30-year-old had started all 19 of the team’s games in which he was scheduled to pitch, totaling 98 innings, the second-most on the club.
His durability, however, was accompanied by unusually difficult results. Gallen carried a 6.34 earned run average, the highest among qualified major league starters, while additional advanced metrics also reflected his struggles throughout the season.
The decline has been particularly noticeable in his ability to generate strikeouts. After consistently posting strikeout rates above 21 percent during previous seasons, Gallen’s strikeout percentage has fallen to a career-low 13.9 percent, accompanied by just 5.60 strikeouts per nine innings.
Opposing hitters have also enjoyed far more success against several of his signature pitches. His four-seam fastball has been hit hard throughout the year, while both his curveball and slider have produced disappointing results according to advanced tracking metrics. He has also surrendered home runs at the highest rate of his career, making it difficult to regain the consistency that previously established him as one of the National League’s top starters.
2. Rotation Depth Faces Another Challenge
Gallen’s injury further weakens a pitching staff that has already absorbed several significant losses this season. Arizona has spent much of the year adjusting its rotation because of injuries to multiple frontline starters.
Corbin Burnes remains sidelined after undergoing Tommy John surgery while also recovering from a teres major strain. Ryne Nelson continues to recover from a flexor strain and ulnar collateral ligament sprain, leaving another important member of the rotation unavailable.
Michael Soroka’s rehabilitation has also progressed more slowly than expected after a recent bullpen session was postponed because of continued recovery from a left glute injury. Without a clear timetable for his return, Arizona’s pitching depth continues to be tested.
As a result, the Diamondbacks are expected to rely on Eduardo Rodriguez, Merrill Kelly, Brandon Pfaadt, Jose Cabrera, and Mitch Bratt moving forward. However, Cabrera was recently optioned to the minor leagues, creating additional uncertainty as Arizona attempts to stabilize its starting rotation after the All-Star break.
3. Opportunity Arrives for Mitch Bratt
With Gallen unavailable, Mitch Bratt receives another opportunity to prove himself at the major league level. The rookie left-hander has impressed throughout the season at Triple-A Reno, earning another chance to contribute during a difficult period for the organization.
Bratt previously appeared in one major league game on June 24 against the St. Louis Cardinals, allowing just one run across three innings. His poise during that outing gave the Diamondbacks confidence that he could provide valuable innings if another opportunity emerged.
Acquired from the Texas Rangers in last year’s trade involving Merrill Kelly, Bratt has continued to develop steadily within Arizona’s farm system. Across 13 starts at Triple-A this season, he posted a 2.41 ERA while demonstrating an ability to miss bats with an impressive strikeout rate.
Despite the growing list of injuries, Arizona’s rotation has still accumulated one of the highest inning totals in the National League, trailing only the Dodgers entering the All-Star break. Maintaining that workload will become even more difficult without Gallen, placing increased responsibility on the club’s remaining veterans and emerging young pitchers during the season’s second half.