This is what a sanctuary city looks like.

A 21-year-old attacker was no match for a 79-year-old north side man living with Parkinson’s. Mike Masterson was able to fight back and help police make an arrest.

Mike Masterson said he was jogging around 5 a.m. near the 2800 block of North Lake Shore Drive on Sept. 29 when police say 21-year-old Rokas Ablacinskas struck him in the back of the head with his fist.

Masterson, a career bartender, was diagnosed with Parkinson’s a couple of years ago. He said he makes a point to stay active, but when he was attacked by the 21-year-old, all that kept running through his head was this is “not how it was going to end.”

Masterson recalled the terrifying moments he was attacked by Ablacinskas in Lincoln Park.

“He kept saying ‘I’m going to kill you, I’m going to kill you,’” Masterson recollected. “My face is all scratched up. I got a lot of black and blue, but you should see the other guy.”

“He punched me in the face. I punched back,” Masterson said. “As soon as I got on top of him, I pushed his arms down, I got up, and started running. I went down to Diversey.”

The 79-year-old made it about one block in front an apartment building.

“He caught up with me because I run slow,” he said, stating the brawl continued until police arrived. “I’m 79, but I’m not a punk. I can handle myself a little bit. I can do 50 push ups.”