A run by the Charles River turned dangerous fast when a Boston man jumped into 40 degree water to save his dog after it chased two geese.

Hans Nagrath was out running with his 2-year-old goldendoodle, Benny, when the dog bolted toward the river and leaped in after the birds.

“I kept calling, ‘Benny, come back! Benny, come back!’” Nagrath told WBZ-TV. “Couldn’t even hear me, didn’t turn around.”

Nagrath said he went in after Benny because “He’s definitely like a son to us.”

But after several minutes in the river, Nagrath said the cold quickly took hold.

“The wind got knocked out of me. I couldn’t really breathe properly, it was so cold,” he said. “I was about 10 feet from Benny when I was like, ‘Oh God, I can’t move my arms and I don’t know what’s going to happen.’”

As he struggled in the water, Nagrath kept trying to keep Benny afloat by pushing up the dog’s hind legs when he started to sink.

The two eventually got close enough to a pier for bystanders to help.

“I was screaming for help,” Nagrath said. “Someone helped get Benny up and then helped me up.”

People nearby wrapped Benny in a blanket after the rescue. Nagrath and the dog survived without serious injuries.

Looking back, Nagrath said the fear of the moment took over.

“I don’t think I’ve ever been more scared in my life and humbled,” he said. “I actually thought I was going to drown.”

He said he now wishes he had first asked someone nearby to call 911 or find a flotation device before jumping in.

The scare also did not seem to change Benny’s interest in geese.

“On the walk home, he was still ready to chase after geese,” Nagrath said. “And I was like no, this is not happening.”

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