Collins and Hightower, their improvement over the past 2 seasons combined has put a player, who most considered a top 5 linebacker, on the outside looking in (probably with a thinner wallet, too) at the starting rotation most likely.
I could be very wrong, but both Hightower and Collins have played better than Mayo did in his previous 12 games, at least as I saw it.
Agree with Chung and Wendell too, both were run out of town (or very close to it) and came back to be key components in making it to and winning the SB.
It was also Wendell's (and Stork's) insertion to the OL that helped save this season back in week 5.