One year ago, at 18:30 BST on 22 April, 2013, the shock news broke - a major doping scandal at the heart of horse racing's biggest global thoroughbred operation.

The powerful Godolphin team called it "a dark day for racing" as 11 of its horses were revealed to have been injected with banned anabolic steroids. Founder Sheikh Mohammed, the ruler of Dubai, was said to be "absolutely appalled".

More positive tests followed, a separate drugs controversy unfolded and two Newmarket-based trainers were banned for a total of 13 years.

BBC Sport examines the changes that have been made to the rules and testing, asks what might happen next and looks at some unresolved questions following a watershed moment for racing.

For the full article click here: BBC Sport