Hector Santiago became the first player to be ejected under MLB's new foreign substance policy. Kamil Krzaczynski-USA TODAY Sports

Seattle Mariners pitcher Hector Santiago on Sunday became the first player to be ejected under Major League Baseball’s new foreign substance policy.

Santiago came on to pitch for the Mariners in the third inning of their game against the Chicago White Sox. He got through two innings without allowing a run, and his glove was inspected after manager Scott Servais removed him with one out in the bottom of the fifth.

Home plate umpire Phil Cuzzi determined that Santiago had some sort of foreign substance on his glove, so the left-hander was ejected. The glove was confiscated and placed in a sealed bag to be sent off for inspection. You can see the video below:

Santiago had a wry smile on his face as he was ejected and appeared to be in disbelief.

MLB began conducting checks on pitchers last week as part of a crackdown on foreign substance use. Multiple pitchers have been furious after being checked, with some even partially undressing on the field to prove they had nothing to hide.

If it is determined that the substance on Santiago’s glove was an illegal one, he will also be suspended.

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