The UFC follow a liturgical order. This means the more important you are, the later your fight appears on the card. Now, the main event is not about Anderson Silva, it is about the Middleweight Championship. The belt, the Crown is always the most important thing.
They have however put Hughes on the card, and you watch, when they are not so happy with the fighters in the main event, they will always put a few fighters on the card that they can trust.
Matt Hughes is their to carry the card in the likely event that Anderson Silva cant manage it. Do you not remember the event just after both Franklin and Hughes had lost their championships...and there was injury and refusal to fight, and before you know it...Franklin and Hughes were plopped into the card...because at the end of the day the inistution knows that they can be trusted.
Hughes is kinda of beyond main event...that is to say, even if you put his name at the bottom of the card, he doesnt need to be atop of the card to get his status...its in his name. This happens when you have a very famous fighter who is begining to make the transition from a famous ufc fighter...to a famous fighter in his own right, completely aside from the UFC...its the difference between Champion, and Legend...a legend is free of the restraints placed upon a champion. Matt Hughes hasnt stopped fighting yet, but he is free of a lot of the restraints that a Champion has placed on him, Hughes doesnt need to be main event because he's a future Legend...unlike most, he's effectively as powerful in notority as, not a Champion...but the actual belt a Champion wears. He is not fighting in the institution, he is becoming a part of its infrastructure....in fifty years time, people will still remember Matt Hughes and thats what I mean....like Royce Gracie...part of the spirit of the person has kinda left an imortal impression on the institution...and before you say its todo with the Hall of Fame...nope...its not....not all in that club are Legends
and I can think of at least one Legend who isnt in that club.
Not all Champions become Legends...Legends in the true sense of the word, dont do anything, they just exist, because they have done all the needs to be done prior. True Legends in the fight world dont fight anymore, just like true legends of old werent really considered legends until they had died.