Minnesota Vikings punter Chris Kluwe says the National Football League (NFL) is becoming increasingly tolerant of gays.

The 30-year-old Kluwe made headlines this week when he came to the defense of Baltimore Ravens linebacker Brendon Ayanbadejo for supporting gay marriage in Maryland.

Both Kluwe and Ayanbadejo have spoken out in support of marriage equality.

But when Maryland Delegate Emmett C. Burns Jr. wrote to Ravens owner Steven Disciotti complaining about Ayanbadejo's advocacy, Kluwe stepped in, calling Burns “mindfucking obscenely hypocritical,” “closed minded” and “totally lacking in empathy” in a letter published on Friday. He concluded a postscript with: “Asshole.”

(Related: Chris Kluwe goes after lawmaker attacking Brendon Ayanbadejo over gay marriage.)

In remarks to The New York Times, Kluwe said the league's attitude towards gay rights was softening.

“I think the culture in the NFL has become a lot more tolerant in the last 10 years or so,” he said. “There's a younger generation coming in every year or two, and they make me hopeful of the future.”

Ayanbadejo said he had received overwhelming support: “I'd say the majority of players are siding with me, that all people have a right to live and love and be happy. … I'm really happy to see the tides changing in the positive.”