As a part of collegiate track team (I was a decathlete) I played basketball and some other sports a couple of times with the team, and it was clear to me that a lot of these athletes wouldn't have had a shot in other sports. Most were soooo uncoordinated.
However, if I look at the metrics of a world class decathlete like Damian Warner, who can run a 10.1 second 100m and a 4:34 1500 and long jump 27 feet and high jump 6'10" and also throw, it's hard to imagine many athletes more athletic than that in other sports.