Getty Images

Thursday afternoon, the free-falling Arizona Diamondbacks will welcome ace Zac Gallen back from the injured list. Gallen has been sidelined since May 7 with an elbow ligament injury that did not require Tommy John surgery, and he will be on a strict pitch limit. The 25-year-old has a 3.04 ERA in five starts this season.

On Wednesday, Gallen spoke to reporters about his return to the rotation, and he also took a shot at MLB senior vice president of on-field operations Michael Hill for the Marlins promoting the use of foreign substances when Hill was in their front office. Hill spent close to two decades in Miami's front office and was their president of baseball operations until being let go last October.

"He was in charge of an organization that was definitely at one point saying, 'Hey, you're going to need these things to help you,'" Gallen told reporters, including The Athletic's Zach Buchanan, without saying Hill's name. "... You can read between the lines."

Shortly thereafter, Hill responded to Gallen's comments (via Buchanan):

"It is predictable that a player represented by a particular agent would make false accusations about me given my current role and the agent's obvious desire to distract people from the current issues surrounding the use of foreign substances. The assertions, however, are completely false."

Gallen is a Scott Boras client and earlier this week Boras called out MLB for abolishing non-rosin foreign substances. "(To) completely abolish gripping agents (other than rosin) creates a major issue as all MLB pitchers were taught (by their respective MLB teams) control of the baseball with the use of gripping substances," Boras wrote.

It's naive to think MLB teams are oblivious to foreign substance use within their organization. It was (and still is, most likely) widespread, and in many cases teams assisted with sticky stuff. Does that mean Hill had direct knowledge of how they were used during his time with the Marlins? Not necessarily, but surely he knew foreign substances were being used by his players.

That said, eliminating (or scaling back on) the use of foreign substances is a worthwhile endeavor. It's one thing to use sunscreen and rosin or pine tar to get a better grip. It's another to weaponize Spider Tack and other substances to improve spin rates and make pitches move in ways they otherwise shouldn't. The pendulum has swung too far in favor of pitchers.

In his capacity with MLB, Hill issued the memo detailing the league's plans to crack down on foreign substances earlier this week. Enforcement will begin June 21 and violators will be suspended 10 days with pay. Not surprisingly, many pitchers are upset at the sudden change, and at least one (Tyler Glasnow) has blamed it for an injury.

Under Hill, the Marlins acquired Gallen in the Marcell Ozuna trade with the Cardinals. Gallen was with Miami from 2018 until being traded to the D-Backs for Jazz Chisholm at the 2019 deadline.