Both shops saw long lines as customers turned out to try Randy's offerings and support Stan's, which has served the community since 1959.
Known for appearances in films including "Iron Man 2" and as the inspiration for a famous donut featured in "The Simpsons," Randy's drew customers who were eager to sample the brand's products.
"Sometimes if you go to a local donut shop, they don't seem to like really do much to it. And this beefs it up," one customer said.
When asked for a verdict, the customer said: "The verdict? Yes, sir. I am not putting the donut away. And this is delicious."
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Some customers waited for hours after arriving Friday morning.
DUSTIN DORSEY: "What time did you get here?"
"Oh, like around 9:45. Yeah. Like, almost two hours now," one customer said.
"We have the glazed. We have the old fashioned and then the velvet. It's really good," said another.
According to Randy's representatives, some people lined up as early as 4 a.m. Friday to receive a free donut and visit the new store.
"It's all about the people. It's all about the local community. Our franchisees have been here part of this community for nearly 25 years," Randy's CEO Mark Kelegian said.
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Local franchise Co-owner Ausaf Masud said the company was confident the area would support both businesses.
"It's a bigger, legendary, iconic brand now coming here for the first time. We all already know that Santa Clara is donut-ready because Stan's is there as well," Masud said.
The opening brought attention to what some described as a "donut corner" of Santa Clara, with Randy's and Stan's located across the street from one another.
At Stan's, customers also formed lengthy lines to support owner Julie Clark and the longtime local business.
"This is the busiest day I think we've ever had -- ever had. We're overwhelmed. We are so blessed and thankful that people have showed up and turned out for us and given us the support," Clark said.
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Customers offered differing opinions when comparing the two shops.
"You can, like, feel like a certain type of nostalgia and just, you know, a happy feeling," one patron said of Randy's.
Another customer praised Randy's variety but preferred Stan's signature offering.
"More selection at Randy's for sure. Sweeter selections, I guess. Stan's has the better glazed donut 100%," they said.
A different customer was even more emphatic.
"Twenty-times better. The texture, it feels like they're making it with love," They said.
As customers continued to weigh in on the newest rivalry in town, both donut shops appeared to benefit from the excitement surrounding Randy's arrival, with crowds filling both businesses throughout the day.