It’s an outrageous amount for a pair of shoes, but it actually fell short of the high end of Sotheby’s expectations. The autographed Air Jordan XIIIs had been estimated to sell for between $2 million and $4 million.

The shoes were gifted by Jordan to the team’s ball boy, who had found the Bulls’ lost jacket earlier that day. Sotheby’s said “this is the only complete pair of sneakers worn by Michael in an NBA Finals game, from any of Michael’s 6 NBA Finals series” that have been authenticated.

They’re also the last pair of black and red Air Jordan 13s that Jordan ever wore on the court for an NBA game.

The price these shoes fetched could be just a warm up for sneaker collectors, though. Sotheby’s also is planning an auction of six shoes worn by Jordan during the six NBA Championship games won by the Bulls in the 1990s.

That collection, called “The Dynasty Collection,” is so rare that Sotheby’s has yet to estimate even a sales range, but some estimates predict the collection will fetch between $20 million and $100 million.

That collection is on a road show right now, having already made stops in Dubai and Hong Kong, with a stop in Singapore scheduled from May 3 to May 6. The precise auction date has not yet been announced.