"There is no pressure. I don't feel nothing like that," he said. "My biggest critic is me. Nobody can ever out-criticize myself. I am just going out there, playing my game. From there, if they like what they like, or don't like what they don't like, it is cool. I know I can always improve on something."
Wyoming features another of the country's top backs, Brian Hill, who is that school's all-time leading rusher. Hill rushed for 1,767 yards and 21 touchdowns this season in 13 games, pushing his career total to 4,194 yards. Hill said last week he won't decide until after the game whether to declare for the NFL draft.
Williams said he won't be trying to out-do his Cowboys' counterpart on Wednesday.
"I'm not worried about anybody else but me," Williams said. "I have watched a couple of games, and he is pretty good, works hard. He is pretty fast and he's got vision and everything. He's just a great player and his offense works for him the same way my offense works for me. So, it is just going to be a great test for us, and hopefully we come out with a W."
Williams is ranked 16th out of 192 draft-eligible backs by nfldraftscout.com, No. 7 on draftcountdown.com's list, and USA Today's draftwire.com lists him "on the bubble" to get drafted. Rankings by SportsIllustrated.com don't mention him and CBSsports.com only recently added Williams, at No. 30.
Scouts who have passed through the BYU football offices "like the prospects that we have," said BYU coach Kalani Sitake. "We have relationships with all of those scouts. So they know that we are going to be honest with them in our evaluations of our players. … So, as they watch our guys, we have prospects, and we will have prospects every year, and I hope we get more and more."
Having played quarterback for 12 seasons in the NFL, BYU offensive coordinator Ty Detmer knows what it takes to reach the next level. He believes Williams "has a great opportunity."
"He's got a great combination of tools he does everything well," Detmer said. "And so talking to the scouts, when they come through, they are really impressed with him. He will have a shot to play at the next level. He's got everything you are looking for in a back. He pass protects well, and that's a big part of it. In the NFL, they want to see those guys be able to pass protect, and he's done a great job with the total package."
Williams has had the fifth- and seventh-best seasons in school history for rushing yards, with 1,233 in 2013 and 1,165 this year. Luke Staley's 1,582 yards in 2001 is out of reach, but 222 yards on Wednesday would move Williams' senior year into second place, ahead of Pete Van Valkenburg in 1972. Williams is sixth on BYU's career all-purpose yardage list, with 4,258.
Having missed three games this year due to an ankle injury, five games in 2014 due to injuries and a suspension and one game in 2013 after suffering a concussion against Utah, Williams couldn't be blamed for wondering what might have been if he had remained healthy.
"I am not really emotional about it and all that. I understand it is my last game and I am grateful for iit, grateful for all my years here," he said. "It just makes me think about how much I've grown, how much experience I've gained, and just a great life that I have been fortunate to live."
Williams and his mother expect more than 100 friends and family members to make the trip down Interstate-15 from their home in Fontana, Calif., to San Diego.
"I am grateful for it to be in a place where a lot of my family and friends can come see me and I am just going to do my best and hopefully we come out with a W," Williams said. "I care a lot about the school, I care a lot about my brothers and everything, so my health is No. 1. I am feeling great. No. 2 is I just want to make sure that we win this game, honestly."