Phelps' magnificent seven

With apologies to Alex Ferguson: swimming, bloody hell. On yet another barely credible day in the sporting life of America's titanic dolphin man, Michael Phelps came from behind yesterday to win the equivalent of a photo finish by a whisker in the 100m butterfly to earn his seventh gold medal of these Games.

That matched Mark Spitz's 1972 record, although when Phelps went to his outsize bed last night he did so in the knowledge that he still had an eighth shot at gold here to come, in the4 x 100m medley relay this morning, Beijing time.

The record books will show that Phelps, 23, won the 100m fly in 50.58sec by a margin of 0.01sec from Serbia's Milorad Cavic. That barely begins to tell the tale of an extraordinary race. Cavic's coach lodged an official protest because he was convinced his man had touched first. Television pictures initially suggested that might have been the case, but it really was too close for the human eye to call.

Swimming's world governing body turned to slow-mo cameras for a decision, and to a back-up timing system. Every method showed 50.58sec on the touch for Phelps, 50.59sec for Cavic. One official calculated that Phelps won by 4.7 milli-metres – in other words, fingertips. Again. That is how Phelps' US relay team won the 4 x 100m freestyle gold earlier in the week.

"When I took that last stroke I thought I lost the race, but it turns out it made the difference," said Phelps.

As well as another Olym-pic gold, the 13th of his career, Phelps earned a$1 million bonus from Speedo for matching Spitz's record. Spitz, now 58, was among those who paid extravagant tribute to his young compatriot: "Not only is Phelps the greatest swimmer of all time and the greatest Olympian of all time, he's maybe the greatest athlete of all time."