The 10-game suspension for Seattle Mariners pitcher Héctor Santiago for violating baseball's sticky substance rules was upheld Thursday by MLB special adviser John McHale Jr.

Santiago will start serving the suspension Friday, when the Mariners open their post-All-Star break schedule at the Los Angeles Angels.

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Santiago was suspended by Michael Hill, the former Marlins general manager who is Major League Baseball's senior vice president for on-field operations, on June 30, two days after the 33-year-old left-hander became the first player suspended under MLB's crackdown on unauthorized sticky substances. Santiago also was fined.

McHale heard the appeal on July 8 in Seattle.

Santiago is in his 10th major league season, his first with the Mariners.

His suspension is with pay. Santiago’s contract calls for a $700,000 salary while in the major leagues and $150,000 while in the minors.

Under a crackdown that started June 21, all pitchers are being checked by umpires during games for illicit grip aids and Santiago was examined as he exited in the fifth inning.

Crew chief Tom Hallion said then that Santiago was ejected for "having a foreign substance that was sticky on the inside palm of his glove." The pitcher said what the umpires found was a combination of rosin and sweat.

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Santiago started this season at Triple-A and made his big league season debut with the Mariners on June 1. He is 1-1 with a 3.33 ERA in 12 games.

Seattle is not be allowed to fill Santiago’s spot on its 26-man roster during a suspension and will play a man short while a penalty is served.