Bryce Petty and No. 17 Baylor needed only 40 seconds to score their first touchdown in the Big 12 opener.

Their big-play offense and high-scoring ways translated just fine into conference play, with a 73-42 victory over West Virginia on Saturday night.

"I just think it's funny how people still say we still have something to prove when we've had four weeks," Petty said. "70 points, I guess, isn't enough."

While it was the rematch of the highest-scoring Big 12 game ever, West Virginia couldn't keep up with the Bears this time. And this wasn't another overmatched non-conference opponent.

The Bears (4-0, 1-0 Big 12) had 864 total yards, breaking the Big 12 record. They had more rushing yards (468) than passing (396) while exceeding the school-record 781 total yards they had in each of their last two games.

"We're just hitting on all cylinders," said Glasco Martin, who ran for two touchdowns. "It's the right scheme, the right players and everything is working for us. It'd be hard to beat this offense."

While playing only one drive into the second half, Petty completed 17 of 25 passes for 347 yards with two TDs and had one of Baylor's school record-tying eight rushing touchdowns. The Bears, shining even brighter with their gold chrome helmets, already had 674 yards while scoring on nine of 10 offensive drives for a 63-21 lead before he was done.

Lache Seastrunk had his eighth consecutive 100-yard rushing game, coinciding with Baylor's winning streak, and he did it without running after halftime. He ran 15 times for 172 yards and two touchdowns, including an 80-yard score as the Bears had 28 points in the first quarter for the fourth game in a row.

"Our players played extremely active and with a lot of intensity and purpose," coach Art Briles said. "That was our plan to play with purpose early. ... We decided just to judge the game by the first half because we felt like we did what we needed in the first half to win the football game."

Based on data available since 1980, STATS said Baylor is the only team to score at least 66 points in four consecutive games.

No other FBS or FCS team has scored 28 points in the first quarter of any three games in a single season since 1996, according to data available to STATS. Baylor still is one game short of matching the Oklahoma in 2008 with five consecutive games scoring at least 60 points.

The Mountaineers (3-3, 1-2), who made their Big 12 debut last year in a 70-63 victory over the Bears, trailed by five touchdowns midway through the second quarter.

"This counts as a loss," coach Dana Holgorsen said. "We'll regroup and we'll do our absolute best to get back on the winning track in two weeks. We've got a lot to work on the next two weeks. I said it all week. If it got into a track meet, we wouldn't be in good shape."

The Bears scored their most points ever in a conference game are 4-0 for the first time since 1991. Their total offense record broke the 807 yards West Virginia had against them last year, and the 73 points were the most for any Big 12 team in a conference game.

The first score came when Petty threw a 61-yard TD pass to Antwan Goodley, who finished with seven catches for 170 yards. West Virginia punted on its first drive, but Levi Norwood fumbled and Karl Joseph recovered in the end zone for a 7-7 lead only 2½ minutes into the game.

While on pace early to match the big-scoring game from last season, Baylor was the only team getting in the end zone for a while.

Petty's 2-yard keeper put the Bears ahead to stay. Right after West Virginia was stuffed for a 2-yard loss near midfield on a fourth-down play, Tevin Reese made a tremendous grab — extending both of his hands above his head and then pulling in the ball while stumbling forward into the end zone — for a 47-yard score.

Baylor needed only play on its next drive to score again, Seastrunk busting free for his long touchdown run.

The Bears were up 42-7 when Martin had 2-yard TD runs on consecutive drives, before West Virginia finally had an offensive touchdown on Clint Trickett's 39-yard pass to Kevin White.

Shock Linwood ran 14 times for 126 yards and a touchdown. Devin Chafin and backup quarterback Seth Russell also ran for scores.

West Virginia scored three times in the fourth quarter, including Darwin Cook's 32-yard interception return with 3 minutes left. Cook had been penalized for targeting earlier in the game, but wasn't ejected after officials reviewed that play.

White had seven catches for 130 yards and two touchdowns, including one from Paul Millard in the fourth quarter.

Trickett, who is West Virginia's third starting quarterback in WVU's six games since Geno Smith went to the NFL, completed nine of 28 passes for 161 yards. Millard was 8-of-13 for 115 yards and two TDs.

Holgorsen described his communication with the quarterbacks as "very average" and that something has to change.

"I'm not doing something right evidently, because there were a lot of times in the first couple of series (with Trickett) where I was giving him specific orders and they weren't being followed," he said. "So I'm not doing something right. I'll keep trying to work on it."