Undefeated boxing prodigy Jose Benavidez Jr. -- who's 25-0 as a pro -- was shot while out on a walk in Arizona early Tuesday morning ... but we're told he's expected to survive.

FYI, the 24-year-old Top Rank fighter is a rising star in the sport -- and recently chalked up a high profile victory over Francisco Santana on the undercard of the Crawford vs. Postol fight in Vegas.

The Phoenix PD confirms the shooting and says the victim was transported to a nearby hospital with non-life threatening injuries.

However, one source with knowledge of the situation tells us Jose's injuries pose a serious threat to his boxing career.

So far, no arrests have been made.

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