CHICAGO -- Héctor Santiago became the first pitcher in Major League Baseball to be ejected for the use of an illegal substance since the league installed mandatory umpire checks for grip-enhancing agents on Monday.

The Mariners’ left-hander was sanctioned in Sunday’s 3-2 win over the White Sox -- thanks to Taylor Trammell's go-ahead homer in the ninth -- after being checked by home-plate umpire Phil Cuzzi and another umpire following a mid-inning pitching change by Mariners manager Scott Servais with one out in the fifth and the bases loaded.

• FAQ: Sticky stuff and new rule enforcement

Sunday’s first game was the completion of Saturday’s contest, suspended in the bottom of the third in a scoreless deadlock due to inclement weather.

• Box score

Santiago and Servais said postgame that the substance the left-hander was cited for was created when legal rosin he used mixed with his sweat, which became more exacerbated on a mid-80s day with humidity approaching 90 percent. The fifth inning was the first instance in which Santiago’s glove was examined on Sunday.

“I wasn't using anything besides rosin,” Santiago said. “That’s what's given to us, because going into this one, once it came up, I was just like, ‘I'm going to use rosin. That's what we got. I don't want this to be a big thing. I don't want this to happen to me.’ And [Cuzzi] said he just felt some stuff sticky on the inside of the glove. So all I used was rosin.”

More specifically, Santiago said he was cited for the substance being in his glove and his glove (right) hand, not for anything on his pitching hand.

“If we're not going to be able to use it on our hands, our arms, to keep that sweat from dripping down our hands, keep that slipperiness off the ball, let's just get it out completely,” Santiago said.

Santiago’s glove was confiscated by Cuzzi and given to an MLB authenticator on site near the home dugout, who placed it in a white plastic bag. The glove was due to arrive in New York on Monday to be evaluated by league officials, MLB.com's Jon Paul Morosi reported. The Mariners believe the inspection will clear Santiago’s name.

They do not believe Santiago will be suspended for 10 days as part of the new protocol that MLB has issued since announcing its intent to crack down on pitchers’ use of grip-enhancing substances, but that has yet to be determined.

“The glove gets sent off, and we'll see where it goes,” said Servais, who was not ejected after pleading Santiago’s case. “But our guys are doing the right thing. They're following the rule. … They can go ahead and look at it. There's no sticky stuff in the glove.”

Tom Hallion was the crew chief and served as the fifth umpire for the day since there were two games, but he was not an active umpire for the first game.

“It was very noticeable, and then the rest of the crew inspected to make sure we were all in agreement,” Hallion said. “All four agreed that it was a sticky substance and that’s why he was ejected.”

Santiago was the first pitcher that the Mariners deployed in the suspended game, taking over in the bottom of the third inning. He cruised through a 1-2-3 third, then worked around a single to Yoán Moncada in the fourth before returning for the fifth, when he issued a leadoff walk to Yasmani Grandal, struck out Jake Lamb and then gave up singles to Yermín Mercedes and Leury García and a walk to Luis González, which prompted the pitching change.

“You just use your judgment on what you would consider is sticky and not a norm for what we have seen over all our careers in baseball,” Hallion said.

“The umpires are trying to do the best they can in a tough situation,” Servais said.

Santiago’s ejection comes in the wake of MLB announcing new guidelines on June 15 to crack down on pitchers using foreign substances. If Santiago is suspended, which would be determined by the Commissioner’s Office, his 26-man roster spot will not be allowed to be replaced by another player.

“I mean, they're going to inspect it and they're going to do all this science stuff behind it,” Santiago said. “It's going to be sweat and rosin, and we'll be all right.”