Zach Arnett physically has no shot in the NFL, yet he's always one of the most dangerous football players in the Mountain West Conference.

It's no surprise he's been trying to prove critics wrong for years, and he's grown to enjoy it.

"This year is the test to see if what people said about being too small is true or not," Arnett said. "I got to play quite a bit last year, but this is my first big opportunity to be a starter and prove myself out there. We're going to see if my size will hold up through a 12-game season."

Don't be surprised if he survives.

Arnett will come to Provo with the 3-3 (1-1, MWC) Lobos after the best game of his fascinating college career.

He had a career-high 16 tackles, a sack and a fumble recovery in a rainy shutout win against Wyoming.

For the season, he's been nothing short of excellent: Tied with Clint McPeek for the team lead with 49 tackles, counting 27 in the past 2 games. And Arnett continues to lead the nation with four forced fumbles -- no Lobo has more than four in a season since NFL star Brian Urlacher (five) in 1999.

While the Chicago Bears linebacker was hardly recruited, he hit massive growth spurts after reaching UNM. Arnett has an athletic background -- grandfather, Bob, led the Lobos in rushing in 1952; uncle Curt had a minor-league baseball career -- but must atone for his genetic lottery.

"Zach has good athletic ability," said UNM coach Rocky Long said. "But mostly, he has a natural instinct that allows him to diagnose plays effectively and get to the ball without running into the big guys. He has a great heart, and he loves the game.

"I think Zach would be successful in any defensive scheme that you put him in," added Long, who has a rarely seen 3-3-5 scheme (five defensive backs) in which Arnett is a crucial signal caller, and mood setter. "He's a little undersized, but he's a good athlete that totally understands the scheme and he would totally understand any scheme. He knows what his job is, he knows where he sits within the scheme and then he plays as hard as anybody on the football field."

BYU head coach Bronco Mendenhall would attest to that. The former UNM assistant could very easily carve out a spot on his team for Arnett, who posts a 3.9 grade point average and carries similar attributes to Cougar defenders.

"He's tough, plays hard and he's certainly has a lot of grit and determination. I've been very impressed with him," said Mendenhall, who met Arnett at the Mountain West Conference media day in July. "After being in that system, size doesn't determine what position you play -- heart does."

Arnett used to have to wait for a play at home plate to find contact.

A local high school standout (La Cueva in Albuquerque), he signed at UNM to play catcher for the baseball team. He received a scholarship for football as a freshman in 2005, when another recruit decided to go elsewhere.

Arnett played both sports upon matriculation before he said it was time to choose. He picked his first love. His second interest wouldn't have been bad, though, as he hit .329 and threw out 13 baserunners during his only college season.