MOSCOW, Idaho -- Last month, Dennis Erickson felt he was coaching a pretty good football team. More important, an improving team.

Two weeks later, the Idaho Vandals have been outscored 113-17 in two games and the veteran coach isn't sure what happened to the team that was last seen battling nationally ranked Boise State deep into the fourth quarter.

Nevada took the Vandals apart from the opening kickoff, piling up a 31-point halftime lead and cruising to a 45-7 Western Athletic Conference victory Saturday in front of an announced crowd of 15,013 at the Kibbie Dome. Fans started filtering out in the second quarter and only a couple of thousand remained at the end.

"After the Boise State game, I felt we were a team that had really, really, really improved," Erickson said. "The last two weeks we've gotten worse. I wish I knew why, but we have. We're not executing on offense like we're capable of. On defense, we've had trouble stopping everything.

"That's the most disappointing thing. We had made a lot of progress and now all of a sudden we've stopped and gone sideways."

Idaho (4-6, 3-3 WAC), routed by Hawaii 68-10 last week, dropped its third straight game and has fallen from a tie for first place three weeks ago into fifth place. To become bowl-eligible, the Vandals must win their last two games. To receive a bowl berth, Idaho will need all kinds of help from other WAC teams.

It was Idaho doing most of the helping Saturday. The Vandals went three-and-out on their first three possessions. Two of those ended with short, low punts. The first, a 32-yarder by T.J. Conley, was returned 33 yards by Joe Garcia to Idaho's 26. That led to Nevada's first touchdown.

The second, a 41-yarder by backup punter Tino Amancio, was returned 33 yards by De'Angelo Wilson with Amancio making a touchdown-saving tackle. Nevada started at Idaho's 34 and was still there two plays later. On third down, Idaho's blitz was handled by Nevada's front and Jeff Rowe threw a 34-yard strike to Caleb Spencer, who slipped behind Stanley Franks.

Idaho trailed 14-0, and quarterback Steve Wichman was intercepted on the ensuing play from scrimmage. A Wolf Pack penalty erased the turnover and the Vandals finally earned their initial first down.

Two consecutive false starts followed -- one in which receiver Wendell Octave ran about 10 yards downfield before the snap. That was followed by a snap that didn't appear to reach Wichman's hands. It looked like a rugby scrum as center Adam Korby had the ball and a wall of bodies pushed him back 4 yards.

Nevada went on top 21-0 when Rowe threw a 30-yard scoring pass to Marko Mitchell, who was closely covered by Kiel McDonald near the left sideline. It went to 28-0 when Wichman, under pressure nearly every time he retreated to pass, was sacked by J.J. Milan, who also recovered the ball at Idaho's 11. Nevada scored four plays later.

Idaho finished the first half with 22 total yards on 24 snaps. The Vandals had six punts and three first downs. They had nearly three times as much penalty yardage (57) as total yardage (22).

"I thought we kept pressure on the quarterback and offensively we were able to throw the ball and Jeff had a great game, so I'm pleased," said Nevada coach Chris Ault, whose team improved to 6-3, 3-2.

The Vandals finally scored midway through the third quarter -- and they needed some good fortune to do so. It appeared Rolly Lumbala fumbled near the goal line, but he was ruled down. On the next play, Jayson Bird scored from the 1 on his only carry of the game.

Idaho had a little success with the running game in the second half, but even that backfired when Tracy Ford fumbled at the end of a 28-yard dash. It went from bad to worse when receiver Marlon Haynes was ejected for apparently punching one of Nevada's players after a Wichman interception. Haynes will probably be suspended for the first half of Idaho's next game.

Nevada's offensive line blew open huge holes in Idaho's front seven in the second half. The Wolf Pack rushed for 167 of their 222 yards after halftime and sophomore Luke Lippincott scored on a pair of 1-yard runs.

Idaho has a bye week before visiting Fresno State on Nov. 18.