Xavier Su'a-Filo was the hulking offensive guard they called "X" at UCLA.
Now he's trying to be an X-factor in the NFL. And in his view, the best way to excel as a pro lineman is to play with a mean streak.
"I watch a lot of the guys I try to pattern my game after," Su'a-Filo said at the NFL Scouting Combine. "I watch a lot of Logan Mankins, left guard from the New England Patriots. He started from Day One in New England, and I love how nasty he is – something about his game that I really try to implement.
"Other guys like (San Francisco's) Mike Iupati and (Washington's) Trent Williams are really mean and nasty. That's what I'm trying to be like."
The 6-foot-4, 304-pounder possesses more than just attitude and size. He boasts experience and athleticism.
Su'a-Filo started all 40 games he played at UCLA, including 13 starts at left tackle as a true freshman. He split time at left guard and left tackle as a junior in 2013 and earned second-team All-America honors to go along with Pac-12 offensive lineman of the year – an award voted on by defensive players in the conference.
Su'a-Filo ran a 5.03 40-yard dash – good for second among guards at the combine. His 4.44 20-yard shuttle time was the best among guards.
"I love pulling, getting out in space," Su'a-Filo said.
The NFL loves guards with that capability. Three of them were taken in the top 20 of last year's draft.
"That was a big deal," Su'a-Filo said. "Nowadays in the NFL as an offensive lineman, if you can be athletic, if you can move, or at the guard position if you can be more flexible and you can play multiple positions, then you're more valuable to a team. So I think it really just got me excited to work harder and have an opportunity to go high."
Many believe Su'a-Filo will be a first-round pick, and if that's the case, he'll be expected to step in and contribute against skilled, stout defensive linemen the moment he first steps on the field.
The Pac-12 – and one opposing defensive tackle who now suits up for the Panthers – helped prepare him for that grade-A challenge.
"Toughest guy I faced in college? Have to say