President Trump is scheduled to honor the Stanley Cup champion Pittsburgh Penguins in a White House ceremony Tuesday that comes as controversies over race, patriotism and freedom of speech have transformed North American professional sports into a political battleground. No Penguins players are expected to skip the White House visit in protest, coach Mike Sullivan said after practice Monday. The team has said since issuing a Sept. 24 statement accepting Trump's invitation that its visit is not intended to be an endorsement of any politician or agenda, Sullivan said. “As I've said all along here, for us, this is not political,” Sullivan said. “The choice to accept the invitation by our organization, to go to the White House, is not political. Nobody's taken a side.” On Sunday, vice president Mike Pence left an NFL game between the Indianapolis Colts and San Francisco 49ers because some players knelt during the national anthem. “I left today's Colts game because President Trump and I will not dignify any event that disrespects our soldiers, our flag or our national anthem,” Pence said in a statement. Trump later said via Twitter that he asked Pence to leave if any players took a knee.