Could you identify one horse from the other?
The 'wrong horse' won a race at odds of 50-1 at Great Yarmouth on Thursday. The two-year-old Mandarin Princess was declared the winner, when in fact it was its three-year-old stablemate Millie's Kiss.
Trainer Charlie McBride says he was "stressed and rushing" after being delayed collecting the saddle, but how easy was it to make that mistake?
Do you know your Red Rum from your Best Mate? Take this quiz to see if you can guess these famous horses just from a headshot...