POCATELLO — With one quarterback in his fourth year, another in his third day and a defense that had to accommodate both, the Bengals clicked better than they have all summer.

Idaho State’s offense traded blows with the defense in an evenly matched scrimmage Saturday at the ICCU Practice Fields. The defense nabbed two interceptions — one of which was returned to the end zone — and special teams disrupted a field goal attempt, while the offense scored on its second drive and found the end zone with both the first- and second-string units.

“They got some turnovers, and that was good,” ISU head coach Rob Phenicie said. “The kids came out and played hard.”

Though the Bengals added quarterback No. 6 to the roster this week, only redshirt junior Tanner Gueller and redshirt sophomore Gunnar Amos played in the scrimmage.

Gueller is the incumbent starter and played with the first-team offense, and Amos made his Idaho State debut Thursday after transferring from the University of Idaho.

Gueller threw a long touchdown pass to Isaiah Walter on the offense’s final drive before halftime and hit Tanner Conner in the back of the end zone to cap a series that started in the defense’s territory. Amos led the offense’s first scoring drive, which ended on a short touchdown run by Nehemiah McFarlin, but went 3-and-out, interception, interception on his final three series.

Heck of a grab by Tanner Conner on the fade from Tanner Gueller. #BigSkyFB pic.twitter.com/CQicZ6qLP8

— Madison Guernsey (@MGuernsey_ISJ) August 19, 2017

Tanner Gueller hits Isaiah Walter deep for the score to end the first half. #BigSkyFB pic.twitter.com/ToSBMPQxBk

— Madison Guernsey (@MGuernsey_ISJ) August 19, 2017

Nehemiah McFarlin with a short TD run. Gunnar Amos led 2nd-team offense on scoring drive. #BigSkyFB pic.twitter.com/DgbpODYAot

— Madison Guernsey (@MGuernsey_ISJ) August 19, 2017

Gueller, Michael Goggin, Robert Kvinsland and Drew Cash all played in ISU’s first fall scrimmage. Goggin appeared to be emerging as Gueller’s immediate backup, but the addition of Amos, who spent two-and-a-half years with the Vandals, has thrown the QB depth chart for a spin.

Phenicie said while the defense was full go against Gueller and the first-team offense, Amos went against a dialed-down version of the defense to help him acclimate.

“Gunnar hasn’t had the reps that the other three have had, so we’ve got to see if Gunnar can play,” Phenicie said. “We know what we have in the other guys. That’s why we wanted to have a scaled-back defense against Gunnar just to see him execute when there’s not a lot of stuff going on. Then work him into all the blitzing and all that.”

Amos frequently used his legs to scramble out of would-be sacks but still showed signs of newness. ISU’s offensive coaching staff is giving its new QB pieces of the offense one at a time until he catches up.

“They gave me a short package,” Amos said. “We got through day-one install, and I’ve just been working on getting that down, and that’s all I ran today. I feel really comfortable with it now, so we’ll start picking up more stuff from now on.”

Amos was intercepted by Atoa Fox on a ball that was tipped by Amos’ intended target, and later by Adkin Aguirre, who spun out of a tackle and ran the turnover to the end zone.

Gueller’s non-touchdown drives ended with a punt and missed field goal.

In ISU’s first scrimmage, the offense didn’t find the end zone until after halftime.

“It felt like we were clicking a little bit better from the start,” Gueller said. “We were just a little quicker from the start, instead of taking so long to get into a rhythm.”