The news that former San Francisco 49ers head coach Bill Walsh died yesterday of leukemia isn't photography related, necessarily. But Walsh's career, and the thrilling football he brought to fans of the 49ers, will always be summed up in one picture: "The Catch." The moment in 1982 when Joe Montana rolled out and threw a short pass to Dwight Clark deep in the end zone, thus defeating the Dallas Cowboys in the last minute of an excruciatingly tight game, was caught by many photographers, but none got it the way Sports Illustrated's Walter Iooss did. In fact, I believe that this image stands as the greatest sports picture of all time. There is a case to be made for Nat Fein's photo of Babe Ruth "bowing out" on his retirement day; there is a case for Neil Leifer's image of Cassius Clay standing over Sonny Liston during their 1965 rematch. But "The Catch" has something the other two don't have: Action. And that's what sport is. It is a moment of absolute, nearly sculptual grace, captured. And it is history--the definitive moment when as aging dynasty, Dallas, was beaten by an emerging dynasty. Of course, I grew up in Nor Cal, and I've been watching the Niners since John Brody was quarterback. But can anyone make a case for another sports photo with as much firepower?