There are only two contenders, but for me, the answer is Imran, undoubtedly. The only one to come close was Wasim, who had more natural talent than anyone else of his generation, from any country - the effortless run-up, the extraordinary wrist-action and the ability to extract swing and movement almost at will - Wasim was certainly a remarkable bowler.

However, given this abundant talent, Wasim underachieved drastically. Imran's record is better, despite missing the best three bowling years of his life through injury. He was a slow starter, and had to work very hard on his action, his run-up and his delivery over his first few years, but once he got there, the finished article was exceptional. He performed consistently for over a decade, often shouldering the attack solely on his own shoulders and excelled even when bowling on pitches on which most other fast bowlers (except perhaps Marshall) struggled. Add to that his phenomenal work-ethic and his horse-like stamina, and you have the complete Test bowler. Wasim runs him close, but in my view, Imran edges it.

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A lie can travel halfway around the world while the truth is putting on its shoes
Mark Twain