Complex sentence: Ponsford is the only cricketer to twice break the world record for the highest individual score in first-class cricket, Ponsford and Brian Lara being the only men to score 400 runs in an innings on two occasions.
Split into simpler sentences: Ponsford is the only cricketer to twice break the world record for the highest individual score in first-class cricket. Aside from Brian Lara, he is the only man to score 400 runs in an innings on two occasions.