Sources - Texas Tech to use Castellanos, Hammond vs. Arizona - ESPN

Quarterbacks Thomas Castellanos and Will Hammond will both play significant snaps on Saturday as No. 13 Texas Tech hosts No. 22 Arizona in a matchup with major implications for the Big 12 championship race, sources told ESPN's Pete Thamel.

Castellanos, a fifth-year senior, is expected to receive an uptick in snaps after he didn't make an appearance in the Red Raiders' loss at Cincinnati last Saturday — a decision that coach Joey McGuire said he regretted on Monday.

«That was a total failure by my part of not, at some point, putting him in the game and seeing what he could do,» McGuire said.

Hammond threw for 227 yards on 24-of-37 passing, rushed for 23 yards on 14 attempts and had two turnovers in the road loss as Texas Tech (6-1) didn't score an offensive touchdown until the game's final minute. Hammond currently ranks ninth in the Big 12 in QBR and 11th in total offense.

«We felt like he was growing, and then you go into the Cincinnati game, for whatever reason, we take a step back there,» McGuire said. «Now, it's how can we put us in the best situation?»

Texas Tech is also expected to get running back Cameron Dickey back Saturday after he missed two games with a high-ankle sprain. Dickey has rushed for 242 yards and four touchdowns this season and is listed as probable on the Big 12's availability report.

Castellanos joined the Red Raiders in late August after a Kentucky judge granted him a fifth year of eligibility. The former Florida State, Boston College and UCF quarterback has made 33 career starts and played the first snap of Texas Tech's win over Houston.

He was declared ineligible after a ruling from the Kentucky Court of Appeals on Oct. 2, the day before the Red Raiders' road win at Colorado. He was granted a