Jordan's Chicago Bulls faced the Golden State Warriors on October 29, 1985 -- just three games into his second season as a pro -- when Michael, wearing the black and red Nike Air Jordan 1s, fractured the navicular bone in his right foot during the first half.

MJ left having played just 18 minutes, scoring 12 points. Chi-town won, 111-105, but lost their rising superstar.

Now, the 1s Jordan was wearing during the game -- one size 13 and the other 13 1/2 -- are available for bidding at Lelands ... where the opening bid is $100K.

It's estimated the kicks will ultimately sell for $400-500K ... when the auction ends in late June.

As for the consignor ... his dad was a friend of Jordan's, and was gifted the sneakers after the game. The family held on to them for decades ... until recently deciding to part with the uber-valuable memorabilia.

The kicks have been deemed legit by MEARS, one of the industry's leaders when it comes to authenticating.

At the time, the injury was a huge blow to the Bulls ... evident by how the local newspaper described the injury.

"The worst possible scenario for the Chicago Bulls, their greatest fear, became a cruel reality Monday when X-rays revealed that Michael Jordan, the heart and soul of this up-and-coming franchise, has a fractured bone in his left foot and will be out for at least six weeks."

Jordan ended up missing six months ... not six weeks. Despite Michael's extended absence, the Bulls had a solid season and even made the playoffs.

MJ, who played in all 82 games as a rookie, actually returned late in the season (March 15, 1986) and played in 14 regular season games, and all three playoff losses, too (the Celtics swept the Bulls).

Thankfully, Jordan was able to stay relatively healthy going forward, and the rest is history. 6 titles ... and a legacy as the best basketball player of all time.