The Sorting by priority (1st sort, 2nd sort, 3rd sort and so on)
After the first sort, all other sorts only come in to play if there were any objects with the same name within the first sort.
Your first sort is the User Name. But you have two John Smiths and three Jessica Johnsons. At This point your second sort of say "Home Team" comes into play. It would then sort them in alphabetical order of the home teams. If you had no users of the same name then the sort would not be used at all.
So, if sort #1 has two or more with the same name, then sort #2 comes into play. If sort #2 has two or more with the same name, then sort #3 comes into play, and so on.