Muhammad Ali spent some time with the 1966 West Indians, including a visit to the dressing room at Lord's, while preparing for a world title fight in London (he had two that year, against Henry Cooper in May and Brian London in August).
The obligatory photos of Ali swinging a bat predictably emerged later, although I prefer a shot of him and Sir Garry Sobers having a chat - "The Greatest" with the greatest allrounder.