Donald Trump labels NFL, America 'soft' during rally

Donald Trump has taken on a variety of targets throughout his presidential campaign. On Sunday, the Republican candidate took aim at the NFL.

During a rally in downtown Reno, Nevada, Trump lamented the rise in penalties for head-on-head collisions and praised players such as Dick Butkus, Lawrence Taylor and Ray Nitschke, who used to regularly deliver such hits.

"You used to see these tackles, and it was incredible to watch," Trump said. "Now they tackle -- 'Oh, head-on-head collision, 15 yard' -- the whole game is all screwed up. You say, 'Wow, what a tackle.' Bing. Flag.

"Football's become soft. Football has become soft."

Trump then said football was representative of America as a whole becoming soft.

In recent years, the NFL has implemented various rules aimed at curtailing concussions among players amid rising concern over football safety, such as 15-yard penalties in many cases for head-to-head blows.

Research, including studies by Dr. Bennet Omalu, the U.S. Department of Veterans Affairs and Boston University, has shown a connection between head trauma and the onset of chronic traumatic encephalopathy, a degenerative brain disease found posthumously in players such as Junior Seau and Dave Duerson.

On Saturday, Cincinnati Bengals linebacker Vontaze Burfict dropped his shoulder and hit defenseless Pittsburgh Steelers wide receiver Antonio Brown in the helmet. It was one of two personal foul penalties called against the Bengals on the Steelers' game-winning drive. Brown is in the concussion protocol because of the hit.

Trump said he is frustrated by the rise in penalties in general. He said he doesn't watch the NFL as much anymore, and referees are tossing flags to impress their wives.

"The outcome of games has been changed by what used to be phenomenal, phenomenal stuff," Trump said. "Now these are rough guys, these are rough guys. These guys, what they're doing is incredible, but I looked at it, and I watched yesterday in particular. So many flags, right? So many flags."

Trump did give a shout-out to New England Patriots quarterback Tom Brady: "He's a great guy."

About 3,000 people gathered for the rally held about six weeks before Nevada's Republican presidential caucus.

The Associated Press contributed to this report.