Zac Gallen, who returned to the mound for the Arizona Diamondbacks on Thursday after a stint on the injured list, took a shot at Major League Baseball executive Michael Hill while speaking with the media on Wednesday.

Hill spent close to two decades in the Miami Marlins' front office before becoming MLB's senior vice president of on-field operations prior to this season.

"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 said, without saying Hill's name. "... You can read between the lines."

Hill responded to Gallen's comments shortly thereafter.

"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," Hill said.

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.