Before the first pitch, the 27-year-old made history, too.
Slater joined teammates Jaylin Davis and Mike Yastrzemski, along with manager Gabe Kapler and coaches Antoan Richardson and Justin Viele, in taking a knee during the playing of the national anthem.
Here's how Slater explained his decision after the win, stating "I strongly believe change needs to happen, and believe this is the proper way to demonstrate my beliefs on the subject."
Slater is entering is fourth season in the majors with the Giants while bouncing between Triple-A Sacramento and San Francisco. This offseason, he took on a big leadership role for the Giants and was selected as the unofficial MLB Players Association representative for the clubhouse. It wasn't exactly by choice, but Slater is honored to represent his team.
San Francisco Giants
"When the players union guys came in for spring training, they asked who's our players rep, and (Buster Posey) said, 'Austin Slater,' " Slater told NBC Sports Bay Area's Alex Pavlovic in May on the Giants Insider Podcast. "It was a semi-official election, I guess, if Buster deemed me to be the players rep. Crawford did as well.
"Obviously I feel blessed and lucky to be supported by those guys. Obviously our locker room has a lot of veterans, and that they trust me like that, it means a lot to me for sure."
The Florida native is taking the role head-on. He didn't say if he will continue to kneel or not, but until he shows otherwise, one can assume Slater will go along with his peaceful protest.
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