Complex sentence: In 1963, he really came to notice when he won his first PGA Tour event in the United States, the Houston Classic, the first PGA Tour event won by a left-handed golfer.
Split into simpler sentences: In 1963, he really came to notice when he won his first PGA Tour event in the United States, the Houston Classic. Charles' win at that tournament marked the first PGA Tour event to be won by a left-handed golfer.