Complex sentence: Messi became the first player to top-score in four successive Champions League campaigns He set the European record for most goals scored in a season during the 2011--12 season, with 73 goals.
Split into simpler sentences: Messi became the first player to top-score in four successive Champions League campaigns. Messi set the European record for most goals scored in a season during the 2011--12 season, with 73 goals.