Complex sentence: Back on home soil he was entered in the Gimcrack Stakes at York in mid August but, after a torrential overnight downpour turned the going into a quagmire, his trainer wanted to scratch him from the race.
Split into simpler sentences: Back on home soil, he was entered in the Gimcrack Stakes at York in mid August. After a torrential overnight downpour turned the going into a quagmire, his trainer wanted to scratch him from the race.