Complex sentence: Cardeñosa retired at almost 36, then took up coaching, mainly in the region; he started as a youth manager at Betis, and had two meaningless stints with the first team, namely in 1990--91's topflight-seven matches, with eventual relegation.
Split into simpler sentences: Cardeñosa retired at almost 36, then took up coaching mainly in the region. He started as a youth manager at Betis, and had two meaningless stints with the first team, namely in 1990--91's top flight-seven matches, with eventual relegation.