Tennis legend Ivan Lendl -- the former #1 ranked player in the world and 8x Majors winner -- is unloading his INSANE Connecticut mansion ... and the 445 acres of land it sits on!!
TMZ Sports has learned the 61-year-old retired Czech-American tennis star listed the Cornwall, CT estate -- about a 2-hour drive from New York City and Boston -- and it's absolutely breathtaking.
Asking price ... $16.45 mil!!
The 18,000 square-foot mansion boasts 10 bedrooms, 15 bathrooms and comes with every ridiculously lavish amenity you could ever want in a home.
We're talking a full gymnasium, workout room, 2 locker rooms, sauna, granite outdoor pool, fishing pond, barn with horse paddocks ... and of course, a tennis court!!
If you're not familiar with Lendl -- who retired in 1994 -- he's one of the greatest tennis players of all-time. In fact, he was ranked the #1 player in the world for 270 weeks.
IL racked up 144 career tourney wins ... including 8 Grand Slam singles titles. He won the US Open and French Open each 3 times and the Australian Open twice.
You're probably asking ... how'd he afford this gorgeous house?!
Well, the Tennis Hall of Famer reportedly made $21 mil from prize money alone (he's also been super successful off the court).
And, if Lendl gets his asking price ... he'll be depositing 16 more M's into his bank account.