BOULDER, Colo. (AP) Mel Tucker's halftime message was simple: We've taken their best shot. Now, let's go give them ours.

Colorado hadn't touched Nebraska quarterback Adrian Martinez, whose jersey was clean and whose passing was perfect, and the Buffaloes had managed just 84 yards of offense and none on the ground.

''When we went out into the tunnel coming out for the second half, those guys were energized and ready to play ball,'' Tucker said.

In a scintillating comeback, the Buffaloes overcame a 17-0 halftime deficit in Tucker's first home game and sent fans streaming onto the field in celebration.

James Stefanou's 34-yard field goal gave Colorado its first lead in overtime and the Buffaloes beat 25th-ranked Nebraska 34-31 on Saturday when punter Isaac Armstrong's 49-yard try sailed wide right .

The students stormed the field celebrating the Buffaloes' second straight win over their old Big 12 rival. Colorado rallied to win in the closing minutes last year in Lincoln.

''This is one of the hardest losses I've ever been a part of,'' said Nebraska's second-year coach Scott Frost, who fell to 0-6 on the road.

Before Saturday, unranked Buffaloes teams were 1-22 all-time against ranked Nebraska teams with their only win coming in 1986 when the Cornhuskers were ranked third.

Rank this one right up there with that one.

It included the longest touchdown in Colorado's history, a 96-yard flea-flicker from Steven Montez to K.D. Nixon in a frenetic fourth quarter that featured 38 points and began with Nebraska (1-1) up 17-7.

Pressed into kicking duties because the starter, Barret Pickering, was out with an undisclosed injury, Armstrong was perfect on four extra points and nailed a 26-yard field goal during regulation.

When Mustafa Johnson sacked Martinez for the third time, this one for a 7-yard loss on third-and-9 in overtime, suddenly Armstrong was facing a 48-yard try.

''I knew we didn't have a kicker,'' Frost lamented.

It was never close as the kick went low and right off Armstrong's foot. That prompted CU fans to storm the field and leave the stands a sea of red. A good 40 percent of the sellout crowd of 52,829 was cheering for the visitors in Nebraska's first trip to Folsom Field in a decade.

''There's a lot of red that left here disappointed,'' Tucker said.

FLEA FLICKER

Running back Alex Fontenot took the handoff near his own goal line, flipped it back to Montez, who backpedaled several steps into his own end zone before letting loose on a deep pass to Nixon.

Catching the ball at his own 40, Nixon slipped a diving tackle attempt by cornerback Cam Taylor-Britt at midfield and raced the rest of the way untouched.

''Talk about just the guts to call that on our own 4,'' Montez said. ''I mean, just guts from (offensive coordinator Jay) Johnson to send that down to us and we got the exact coverage we want ... They thought we were going to hand it off and run it, so we hand it off, pitch back, K.D. was screaming wide open so I just tried to give him a ball he can run with.''

TALE OF TWO HALVES

Martinez completed all nine of his passes for 180 yards in the first half. The second half included six sacks, an interception, and 7-for-15 passing for 110 yards.

After struggling in the first half, Colorado's offense piled up nearly 300 yards and 34 points in the third and fourth quarters.

''First half I thought it was over with,'' Nebraska linebacker Mohamed Barry said. ''I thought it was going to be a blowout. That's the way it should have been. We had them. We were better than that team and the second half we didn't finish. We have to finish.''

ROLLER COASTER

Martinez, who replied to Colorado's 96-yard TD with a 75-yard TD strike to running back Maurice Washington on the very next play, gave Nebraska a 31-24 lead with a 6-yard keeper on fourth-and-1 with 5:49 left in regulation.

Laviska Shenault fumbled after a 54-yard return when Taylor-Britt punched the ball out, but the Buffs forced a punt and Montez hit Tony Brown with a 26-yard scoring strike with 46 seconds remaining in regulation.

THE TAKEAWAY

Nebraska: The Huskers dominated the first half, putting together TD drives of 96 and 95 yards that began with Martinez in his own end zone. But maybe the altitude finally caught up to a Nebraska team that's no longer used to it.

Colorado: The Buffaloes are now 2-0 in the Mel Tucker era with wins over rivals Colorado State and Nebraska and Air Force up next weekend.

POLL IMPLICATIONS

The Cornhuskers never trailed in regulation but their loss in Boulder could bump them out of the Top 25.

UP NEXT

Nebraska hosts Northern Illinois on Saturday.

Colorado hosts Air Force on Saturday.

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