Complex sentence: In 2015, the club had its most successful period in its history under the guidance of Argentinian Osvaldo Escudero, the club were able to win their first championship (the Clausura 2015) in the club history.
Split into simpler sentences: In 2015, the club had its most successful period in its history under the guidance of Argentinian Osvaldo Escudero. The club were able to win their first championship (the Clausura 2015) in club history.