CHICAGO (CBS) — Cubs first baseman Anthony Rizzo on Thursday blasted the “losers” who have been criticizing the survivors of the Parkland school shooting for seeking tougher gun control laws. Hours later, Rizzo belted a home run in the team’s season opener in Miami.

Rizzo said he attended the Stoneman Douglas High School baseball game on Tuesday night, and was excited to see the team cruise to a 15-0 victory. But his pride in his old high school team pales in comparison to his respect to the students who have become leaders of the growing gun control movement in America after a gunman killed 17 students and teachers at the school last month.

“I think it’s amazing. I think that these kids are standing up for what they believe in. They’re motivating everyone to go out there and register to vote, which is amazing, because that’s as powerful as they can make their voice heard is going out and vote,” Rizzo said of the survivors of last month’s deadly shooting at Stoneman Douglas High School in Parkland, Florida.

Rizzo, who starred on the Stoneman Douglas baseball team when he was in high school, said “it’s crazy to hear” some people call the shooting survivors “crisis actors” who pretend to be victims to drum up support for tighter gun control laws.

“I think they’re losers, that’s what I think,” Rizzo said of such conspiracy theorists. “You hear all these things, and it’s like how can you even say this. Where is your heart? Where is your sense of sympathy? You know, it’s as real as it gets. You don’t think it’s real, go there.”

He also said he knows the Parkland survivors won’t be intimidated into giving up their fight for stronger gun control laws.

“For them to be getting bullied on Twitter by some guy with strong fingers, I think it’s pretty funny. I know for a fact that they’re not going to let anything affect them in their mission, because what they’re doing is bigger than themselves, and it’s for a lot of people,” he said.

Rizzo said he was proud to see the Parkland survivors leading the March for Our Lives rally in D.C. last weekend.

“They’re holding the throttle down on all these politicians, and holding them accountable for what they believe in, and it’s just unbelievable how an entire nation is rallying around Stoneman Douglas High School,” he said. “I think that the nation is listening. I think that there’s some politicians that are maybe shaking a little bit, a little nervous.”

The Cubs were in Miami on Thursday for Opening Day against the Marlins.

The team wore Stoneman Douglas #MSDStrong t-shirts during warmups, and the Cubs and Marlins both wore patches honoring the Parkland victims on their uniforms during the season opener. In the second inning, Rizzo belted a home run to right field.

On Friday, some Stoneman Douglas survivors will throw out the ceremonial first pitch at Marlins Park.

“Tomorrow will be a tough one to see that, I think, for everyone who has a pulse, but it’s really cool how the Marlins have supported Douglas, and how every pretty much sports franchise had, and it’s really really cool to see,” Rizzo said.

For his own part, Rizzo said he thinks the nation needs stricter gun control laws, in particular when it comes to background checks for buying firearms.

“I think it’s a little too easy to go in there and get a gun. I think pretty much the entire nation can agree on that,” he said. “If you can make it harder to get guns, hopefully it eliminates a little bit of the problems.”

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