The San Francisco 49ers is one of the NFL's two undefeated teams this season -- but is a French bulldog partly responsible for their most successful start in 29 years?

One-year-old Zoë, the NFL's first-ever emotional support animal, was adopted by the 49ers and has made an immediate impact with the California team by helping some players cope with mental health struggles.

“This is a very stressful job, it’s very hard for a lot of guys,” 49ers defensive end Solomon Thomas said in August, per the Athletic. “A dog could be a perfect getaway for some guys, and sometimes you don’t know what a dog could mean."

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Thomas has openly discussed his mental health struggles since his sister committed suicide back in January 2018. He says having Zoë around helps him relax no matter what type of mood he's in.

“Anytime I go in there and see her, it’s just really relaxing,” Thomas told the outlet. “I can have a good practice or come in there really mad, or come in really sad, and Zoë races over to me. I can just play with the little puppy for 10 or 15 minutes; that just kind of resets my day and lets me put everything back into perspective."

Zoë is even becoming a celebrity pup online. She has her own Instagram account with more than 6,400 followers called "the49ersfrenchie," which shows her interacting and playing with teammates at Levi's Stadium.

She was given an invite to become an official 49er after an employee brought her brother's French Bulldog, Vito, to work one day. Players reportedly loved Vito, which led Austin Moss, the director of player engagement to find a dog who could help players de-stress every day.

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That dog turned out to be Zoë.

“Given this environment and how stressful it is whether, you know, it’s you’re trying to make the team or just the daily grind of being a player, we found that it has brought a lot of value to the total wellness portion,” Moss said, according to the Athletic. “In player engagement, one of our main pillars is total wellness -- mental health, physical health, emotional health. Zoë’s been a great addition for us and we’re seeing some positive results from it.”

Zoë can regularly be seen in her Instagram account being cradled and kissed by normally intimidating NFL players. She also routinely hangs out in her massive bean bag chair, a place players can sit on while relaxing with her.

Before a game against the Seattle Seahawks last year, offensive tackle Joe Staley even held up the French bulldog with two arms to replicate Simba in the opening scene of the 1994 Lion King movie.

Now it looks like Zoë is there to stay.

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“Football is so all-in, to have a place for them to go and kind of unplug, that was a good thing," general manager John Lynch told the outlet. "I finally told our owner after a month. I said, ‘Hey, we kind of have this dog now and the guys really like it.'"