STILLWATER, Okla. (AP) -- J.W. Walsh was picked to start at quarterback for Oklahoma State on Saturday against Texas-San Antonio.
Clint Chelf started the Cowboys' opener against Mississippi State, but as expected Walsh also played in the 21-3 victory.
Coach Mike Gundy named Walsh the No. 1 quarterback on Monday.
"I think he just brought a spark to our team," Gundy said. "I felt like there was a lift when he came in, for whatever reason."
The sophomore from Denton, Texas, was 18 of 27 passes for 135 yards, and rushed for 125 yards and a touchdown.
"When we started clicking with all the zone read stuff and the up-tempo stuff, that's what we stuck with," said Walsh, whose previous best rushing performance was 73 yards. "A lot of it was just designs on read plays that we had just put in, that we had worked on all offseason, and for the first time to run it and be that successful with it, that was good to see."
Gundy said he is unlikely to take Walsh out at all now.
"We started to see results from what J.W. was giving us," Gundy said. "And at that point when you're playing a team that has the capability of beating us, we need to stay with what we thought gave us the best chance to win the game. J.W. is our quarterback now. Clint could play. I'm not sure we have a time frame for that, I'm not sure we ever will. We're comfortable with the way that J.W. played and we think that he gives us the best opportunity for success."
As well as Walsh was running the offense, the team's leading receiver, Josh Stewart, gained just 39 yards on four receptions. OSU's only completed pass over 20 yards was Walsh's throw to Stewart for 21 late in the first half.
"In most cases, on defense, safeties have to help on quarterback run and if safeties help in quarterback run, it gives you a chance to throw it downfield," Gundy said. "There's a number of areas as an offense that we need to improve on, and that's one of them."
Walsh said knowing he's going to be the starter all week will not alter his mental approach as he gets ready to face UTSA, which won at New Mexico 21-13 in its opener Saturday.
"There's not going to be much of a change, because any time I'm preparing for a game, you have to prepare like you're the starter," said Walsh, who is currently the Big 12's leading rusher. "No matter where you are on the depth chart, you have to prepare like you're one play away and that you could be in the game at any moment, so that when you do get your opportunities, you can go in and play."
As a quarterback with the ball in his hands a lot, Walsh has had to adjust his mindset when he runs to preserve his health.
"For a long time, I've had family members and friends tell me, `When you run the ball, get out of bounds, get down,' but I kind of just ignored it for the most part, because that's just how I ran the ball," said Walsh, who scored seven rushing touchdowns while earning Big 12 Freshman of the year honors last year. "But now, especially after getting hurt last year, I realize I have to play much smarter and take care of my body when I'm running the football."
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