"I've gotten everything from support to threats," Maxwell said after the A's defeated the Rangers, 8-1.
"I mean, I expected it, it's nothing different that I haven't dealt with in my life. I mean the threats that I'm getting are part of the problem."
The A's remained firm in their support of Maxwell, with manager Bob Melvin praising the rookie for the way in which he has gone about informing his teammates, the coaching staff and front office of his intentions and reasoning.
"He couldn't have handled the communication leading into that better than he did," Melvin said. "I think the last thing everybody wanted was to be surprised by something like that, because we all know we're going to be asked questions about it. Not only did he communicate what he was going to do, but he went into the reasons for it.
"It made it a more comfortable situation and today, after what transpired yesterday, is certainly business as usual."
Outfielder Mark Canha, who had a hand on Maxwell's shoulder during the anthem on Saturday and Sunday and plans to continue to do so as Maxwell plans to continue to kneel, said he isn't going to kneel with Maxwell, but added he thinks it "would be great" if other baseball players kneeled as well.
"I think it's a small step forward, but I think we're starting to move in the right direction as a country when it comes to fighting for what's right," Canha said.
Maxwell is willing to do just that and understands the potential ramifications.
"I've talked to our superiors and they understand why I'm doing it and they respect the fact that I am doing it. If it ends up driving me out of baseball, then so be it," Maxwell said. "This is bigger than a monetary standpoint, this is bigger than the uniform I put on every day. This is about the people in this country and we all deserve to be treated equally, and that's the whole purpose of us taking a knee during the national anthem."
While Maxwell is still unavailable to play because of a concussion he suffered when a foul ball hit him square on his catcher's mask Wednesday in Detroit, Melvin said he could return to the lineup as soon as Monday.
"He is feeling much better today," Melvin said. "He's going to go through some tests later on today, and if he passes that and is feeling much better, than the potential for him to play tomorrow is there."
Alex Simon is a reporter for MLB.com based in the Bay Area. Follow him on Twitter at @alexsimon99. This story was not subject to the approval of Major League Baseball or its clubs.