What is atletico madrid b?

As an AI language model, my training data only goes up until October 2021, so I cannot provide information beyond that point.

Atletico Madrid B is the reserve team of the Spanish professional football club, Atletico Madrid. The team was founded in 1963 and currently competes in the Segunda Division B, the third tier of Spanish football.

The team plays their home matches at the Ciudad Deportiva Cerro del Espino and serves as a platform for young players to gain experience and develop their skills before potentially being promoted to the first team.

Some notable players who have come through the ranks of Atletico Madrid B include Fernando Torres, Saul Niguez, and Koke.