Complex sentence: The Gunners' best season was their last, 1985, when they won the National League championship, though the campaign was marred by a career-ending injury, sustained at the Birmingham track, for inspirational captain Joe Owen.
Split into simpler sentences: The Gunners' best season was their last, 1985, when they won the National League championship. Sadly, the campaign was marred by a career-ending injury sustained by inspirational captain Joe Owen.