Lynne Sladky/Associated Press

Oakland Raiders running back Marshawn Lynch turned heads Sunday before his team's game in Mexico City against the New England Patriots.

As Ben Volin of the Boston Globe passed along, Lynch sat during the United States national anthem but stood during the Mexican version:

The notion of NFL players protesting racial inequality and police brutality in the United States by kneeling or sitting during the national anthem started last season when then-San Francisco 49ers quarterback Colin Kaepernick did so.

While Kaepernick is a free agent and still unsigned despite being 30 years old with a Super Bowl appearance on his resume, a number of players—including Lynch—have protested during the 2017 season.

The issue was at the forefront of the headlines in Week 3, especially when more players knelt than usual after President Donald Trump made disparaging comments at a rally, suggesting owners should "get that son of a bitch off the field right now" if players didn't stand.

As for Lynch, Raiders coach Jack Del Rio discussed his running back's approach after a preseason contest, per NFL.com.

"On Marshawn, talked to Marshawn trying to make sure we're on the same page," Del Rio said. "He said, 'This is something I've done for 11 years. It's not a form of anything other than me being myself.' I said, 'So you understand how I feel, I very strongly believe in standing for the national anthem. But I'm going to respect you as a man, you do your thing. We'll do ours.' It's a non-issue for me."

Lynch standing for the Mexican national anthem came on the same day NFL Vice President of Football Communications Michael Signora announced the league and the Mexico Ministry of Tourism agreed to continue playing NFL games in Mexico through 2021.