Kate Upton & Justin Verlander Score Massive Bev Hills Mansion

Justin Verlander and Kate Upton are getting the martial house ready to go ... because they just locked up a sweet Bev Hills mansion for $5.475 mil ... and it comes with its own private tennis court!

The Detroit Tigers pitcher proposed to his supermodel girlfriend back in May -- and we're told the house hunt began shortly after.

Now, we've learned they pulled the trigger on a 5 bedroom, 6 bath East Coast country style home ... it's 5,000 square feet with an enormous pool and hot tub, koi ponds, park area to entertain guests ... and much, much more!

We're told the couple closed the deal on the private gated estate back in October. Judy Feder and Susan Smith of Hilton & Hyland represented the seller.

Unclear if the couple is planning on moving in until after the wedding ... but would you let this place sit vacant?? Hell no!