Complex sentence: Nowadays it is almost unheard of for a professional cricketer to face a fast bowler without a helmet, and in under-19 cricket they are compulsory for all batsmen and any fielder within of the bat.
Split into simpler sentences: Nowadays it is almost unheard of for a professional cricketer to face a fast bowler without a helmet. In under-19 cricket they are compulsory for all batsmen and any fielder within of the bat.