I'll admit I'm not a huge sports fan, but I am a huge numbers fan, and sports produces a lot of those. It also produces a lot of analysts: after all, there's lots of money riding on much of these numbers. So it's a bit of a challenge to find something original, and by definition it's going to be a bit frivolous.
It occurred to me that if teams keep retiring numbers and don't expand the pool of possible numbers, eventually they will run out. A bit of Googling revealed that the Boston Celtics have the most retired numbers of any major professional sports team. The NBA allows 100 numbers, from 1 to 99 and 00; they've retired 21 in the past 40 years, so a simple linear fit shows that at this rate they will run out in a couple of centuries.
I wouldn't worry about this problem too much; the Celtics have already shown how to solve it. When they retired Jim Loscutoff's jersey, he requested that they not retire his number (18), so their banner reads "LOSCY" instead. Later, Dave Cowens spoiled the gesture by wearing the same number and having it retired.