Well, it says mandatory challenger, but I must say that Crawford should step up his competition. Bob Arum really knows how to protect his cash-cow.
We have been talking about a potential clash between the 2 best welterweights, Spence Jr and Crawford. However, we don't know if this can happen in the future though.
Bob Arum is still the best promoter when it comes to match making and creating superstars. But this isn't hiding Bud from the other 147 champs. Crawford himself and Bob knows that they are favorite to beat any of the other 147 champions and stars. This is the reason why Bob is always trying to negotiate with Haymon to make the Crawford-Spence fight.
On the other hand, Haymon knows he got most of the big names at 147. He knows they are all underdogs against the p4p king (Crawford). This is why Haymon won't answer any calls from Bob. Haymon is protecting his assets thus depriving us especially Crawford vs Spence.
My opinion, Crawford will smash the other 147 champions.