AMES, Iowa -- Skyler Howard threw five touchdowns, four on deep passes, and freshman running back Martell Pettaway made the most of a late-season debut as No. 18 West Virginia buried Iowa State 49-19 on Saturday.

Showing no hangover from a loss to Oklahoma that knocked them out of the Big 12 title race, the Mountaineers (9-2, 6-2) piled up 613 yards. Howard's 12-of-21 passing accounted for 330 of those, including touchdowns of 71 and 40 yards to Shelton Gibson, who finished with 161 yards on three catches.

Howard also tossed a 48-yard score to Marcus Simms and a 34-yarder to Ka'Raun White, ruining senior day for Iowa State (3-9, 2-7).

"(Iowa State) is tough to beat like we beat them, so I'm proud of the way we did that," said West Virginia coach Dana Holgorsen.

The fourth-string running back Pettaway, slated for a redshirt season until being pressed into action Saturday, ran for 181 yards and a touchdown on 30 carries.

"Pettaway had to go play. We don't win this game without him playing," said Mountaineers running backs coach Ja'Juan Seider. "He was willing to go in there and sacrifice. He didn't care about a redshirt. All he thought about was getting in there and helping his team win."

West Virginia scored 21 points off four Cyclones turnovers, including the league-leading eighth interception by cornerback Rasul Douglas, who also forced a fumble.

Jacob Park finished 23-of-44 passing for 371 yards for Iowa State while David Montgomery ran for 141 yards on 21 carries. Both players lost second-half fumbles when WVU outscored the Cyclones 28-3.

"I thought we did some really good things at times, but obviously our inconsistency hurt," said Iowa State coach Matt Campbell. "Turning the ball over four times within the 50-yard line against a team like that, it's going to really prohibit you."

Alert to an Iowa State onside kick, WVU capitalized on Howard's touchdown to White for a 7-3 lead. Kennedy McKoy followed with a 3-yard touchdown run, set up by Gibson's 50-yard grab to make it 14-3.

Iowa State crossed midfield on 12 possessions but scored only one touchdown -- Kene Nwangwu's 97-yard kick return.

Mike Warren lost a fumble at West Virginia's 46. Allen Lazard couldn't bring in a low fourth-down pass at the 39. Douglas intercepted Park at the 30. Montgomery was stripped by Douglas at the end of a 46-yard run.

All the Cyclones' offense could show for 561 yards were Cole Netten field goals of 32, 28, 40 and 31 yards.

"We gave up yards, but that's going to happen. It's Big 12 football," said West Virginia defensive coordinator Tony Gibson. "But if you can tell me every week we'll give up four field goals, we'll take it. I don't care if we give up a thousand yards."

Notes: West Virginia turned to Pettaway after losing its top three RBs. Justin Crawford left with a right leg injury after seven carries for 29 yards. McKoy exited after two carries, and Rushel Shell did not dress. ... Lazard's sixth 100-yard receiving game set an Iowa State single-season record. ... Mountaineers TE Trevon Wesco's first career catch resulted in a 6-yard fourth-quarter touchdown. ... The Cyclones fell short of their first three-game Big 12 winning streak since 2005.