Complex sentence: In international club football, Atlético has won the Copa Libertadores and the Recopa Sudamericana once each, and a record two Copa CONMEBOL; the team has also reached three other continental finals.
Split into simpler sentences: In international club football, Atlético has won the Copa Libertadores once, the Recopa Sudamericana once and the Copa CONMEBOL twice, more than any other club. The team has also reached three other continental finals.