Leszno

The Derby Wielkopolski against Enea Basket Poznań is the fixture that matters most to Polonia 1912 Leszno, two clubs from the same region. Polonia's basketball side has spent most of its history since forming in 1947 inside the wider Klub Sportowy Polonia 1912.

The 2015/16 season stands apart. Polonia beat Dacka Pelplin to win the Puchar Polski PZKosz, the cup competition for the lower leagues, and followed it by reaching the II Liga playoff final, where AGH Kraków beat them to the title but not to promotion — Polonia went up to the I Liga regardless. Before that, the closest points of reference sit decades back: third place in the II Liga in 1952, and a run to the last sixteen of the Polish Basketball Cup in 1954.

The women's section, playing as Jamalex Polonia 1912 Leszno, has reached the top-flight Basket Liga Kobiet in the past, though without a title to show from those years.

Home games are played at Hala Trapez, named after Zbigniew Białas, a ground that seats 640. In red and white, the team known as Biało-Czerwoni now competes in the 1 Liga, the country's second tier.