A 3rd ring is on the horizon for Mookie Betts, 'cause the Dodgers superstar just popped the question to longtime GF Brianna Hammonds -- and she said yes!!!!
28-year-old Betts and Hammonds met way back in middle school ... and have been dating for 15 years. They have a 2-year-old baby girl together.
Of course, Mookie is fresh off winning a World Series ring with the Dodgers (his 2nd WS title) ... but says this is the real highlight.
"Winning another World Series was great, but putting a ring on MY MVP is the REAL BLESSING!