Complex sentence: A month later, he suffered a fatal heart attack at age 55 in Houston, Texas, where he had made his home since his days as player and (later) manager for the Cardinals' longtime Texas League farm team, the Houston Buffaloes.
Split into simpler sentences: A month later, he suffered a fatal heart attack at age 55. Keane had lived in Houston, Texas since his days as player and (later) manager for the Cardinals' longtime Texas League farm team, the Houston Buffaloes.