A lock of hair from Secretariat -- arguably the greatest racehorse of all time -- has just hit the auction block ... and it can be all yours, if you've a bunch of extra cash laying around!!
TMZ Sports has learned ... a 12-inch strand from the thoroughbred's mane that was obtained in the 1980s has just gone up for sale at Lelands -- and, experts there say it could sell for as much as $10,000.
We're told the piece of Secretariat's fur was gathered at Churchill Downs in the late '80s, when a groomer handed it over as a gift for a horse racing fan.