The man, who asked to remain anonymous, told Eyewitness News he had just deposited money at the Wells Fargo at South Gessner and South Braeswood on Nov. 8.
At the time, the 66-year-old said he had no idea he was being watched and later didn't realize he was being followed home.
It's a crime police call "jugging."
The victim soon put the pieces together when a mysterious man appeared in his driveway.
"I said, 'Oh!' You know, I was a little bit startled, and I said, 'Can I help you?' and he didn't say a word," the victim said.
He said the man immediately began peering into his car windows, where he spotted the same bag the victim had used to carry his money to the bank.
"He pulled out a hammer and started hitting the window," the victim said.
The victim said when he threatened to call police, the man began attacking him with the hammer.
"On the fifth blow, he actually broke the hammer on my head. At that moment, I had to think about my father, who always said that I had a hard head."
The force brought him to the ground but didn't bring his attacker closer to getting his hands on any cash.
"When I went down, I dropped my phone and the hammer's now broken, he doesn't have a weapon so he decides, I guess in a panic, to just grab my phone and at least get something," the victim said.
He watches as the thief drives away and later describes the vehicle to the police. This month, they arrested the man.
"He was fully intent to finish me off. That was his full intention, 100%," the victim said.
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