Complex sentence: He took on the fast rising Oliver McCall and refined his style, and was instrumental in the erratic McCall's stunning two round knock out of Lennox Lewis to win the WBC World Heavyweight title in London in September 1994.
Split into simpler sentences: He took on the fast rising Oliver McCall and refined his style. He was instrumental in the erratic McCall's stunning second-round knockout of Lennox Lewis to win the WBC World Heavyweight Championship in London in September 1994.