Nebraska spent much of the fourth period of the Cotton Bowl game dusting off its playground gimmick plays today, then lost in the last 12 seconds on an unintentional Houston "trick" pass that surprised even the grateful Cougars.

On the fourth down from the Nebraska six, Houston quarterback Terry Elston drilled a pass into the end zone. The Cornhuskers' Ric Lindquist should have knocked it down, but the ball caromed off his shoulder and into the hands of Houston's stunned Eric Herring, who was standing just inside the end line.

Herring tipped the ball, then caught it and Kenny Hatfield kicked the conversion to give the Cougars a 17-14 triumph that left the 15,000 Nebraska fans in attendance so shocked that many stayed in their seats long after the game had ended.

It was the seventh time this season Houston had pulled out a victory in the fourth period and the fourth time Elston, a second-stringer, was the pivotal factor. It also was his first touchdown pass of the season.

But this comeback was the sweetest yet for Houston, which lost to Notre Dame on the final play of last year's Cotton Bowl after blowing a 22-point lead.

"At least we played the last minute of this game," Houston Coach Bill Yeoman said, referring to the 1979 defeat. "We've been thinking about that loss for a long, long time."

The final 8 1/2 minutes, which saw 17 points scored, was in stark contrast to the rest of the afternoon. Both clubs spent those earlier minutes grinding out yardage on mainly off-tackle running plays and taking turns kicking 17 punts.

It took some wonderful imagination by Nebraska Coach Tom Osborne to finally excite the fans (there were 8,000 no-shows although 72,032 tickets were sold) and untrack the lethargic affair.

After a 41-yard Hatfield field goal with 8:25 left in the game put Houston up, 10-7, Nebraska got a much-needed turnover at the Cougar 31 to give Osborne a chance to uncork his eye-opening plays.

From a third down at the 23, he had quarterback Jeff Quinn pitch to tailback Jarvis Redwine, who ran three steps to his left before pulling up and lofting a soft pass to Quinn, who had run around right end.

Quinn grabbed the throw for a 13-yard gain. Two plays later from the six, Nebraska ran what Osborne called "a swinging gate."

Quinn lined up over the ball at one hashmark while the rest of the offensive unit set up at the other hashmark. Quinn then picked up the ball and tossed it underhand to Redwine, who caught it behind his offensive line and ran through the befuddled Cougars for an apparent touchdown.

The officials, however, called Nebraska for illegal motion and Houston for offsides, nullifying the play. The officials explained that Quinn, in that formation considered the center, had to throw the ball in a continuous motion but instead picked it up, stopped and then threw it.

So the Cornhuskers went conventional on the next snap. Quinn dropped back, waited and threw to a wideopen Jeff Finn in the middle of the end zone. Houston strong safety Tommy Ebner admitted he had blown his coverage, leaving Finn free to roam.

That touchdown gave Nebraska a 14-10 lead with 3:56 to go. Until that drive the club had not been able to penetrate Houston's 42 in the second half and had not scored since ripping off an 85-yard march in the first quarter.

Houston had not been much more effective after intermission. Despite Elston's repeated second-quarter success at running option plays (he picked up 49 yards in the period), Yeoman stuck mostly in the second half to conservative halfback plays that bogged down every time the Cougars neared scoring territory.

But with time running out, the play-calling became much more unpredictable. The reason Houston got going was Elston, the 6-foot-3, 215-pound junior who has been relieving starter Delrick Brown successfully all season.

Elston, who finished with 87 rushing yards and 119 passing to earn offensive player of the game honors, accounted for the initial first down of the winning drive with a 10-yard pass to Herring at the Houston 49.

On third and four, fullback John Newhouse crossed up the Nebraska defense by running off right guard for 10 yards and another first down.

Another 15-yard pass to Herring moved the ball to the Nebraska 36. But two running plays netted only four yards, setting up a passing situation -- only to see fullback Newhouse break off right guard for 19 yards and a first down at the 20.

Elston immediately found the elusive Herring, a second-stringer himself, for an 11-yard gain on a down-and-out pattern at the nine with 49 seconds left.

On first down, Elston tried to cross up the Nebraska defense with an option run, but was stopped at the five, forcing Houston to use its last timeout with 33 seconds on the clock.

Now the Cougars had to pass. Elston could not find a receiver and had to sprint to his left and dash out of bounds, taking a yard loss in front of the wildly cheering Nebraska rooting section. Twenty-four seconds to go.

Elston dropped straight back and threw for his favorite target, Lonell Phea, near the right end-zone flag. Nebraska's Mark LeRoy made a fine defensive play, however and batted the ball away.

That left 19 seconds and one last Houston down. Elston again dropped back and saw Herring drifting across the middle of the end zone.

"Nebraska was doing a fine job of covering," Elston said. "If it hadn't been fourth and six and time running out, I wouldn't have forced the pass. I guess there was a little luck."

Luck did play a part. Nebraska's Lindquist and LeRoy both were running between Herring and the football when Elston unloaded his desperation pass.

"I hit the ball," Lindquist said. "But I couldn't tell what happened after it hit me. I hit the ball and then ran into somebody (LeRoy)."

Things happened so fast once Lindquist tipped the pass that even Herring was befuddled. He thought no one deflected it but instead "it went right under the guy's armpit, hit my arms, bounded up and I caught it."

The Houston touchdown ended a marvelous 66-yard drive under intense pressure. And it was pulled off by a native of Alabama who was considered too skinny in high school to be recruited as a quarterback by Bear Bryant.

Instead, Elston grew up at Houston from a skinny 190-pounder to a sturdy 215-pound speedster with lightning feet. He hasn't been starting because Yeoman feels that a coach should stick with a senior quarterback (Brown) as much as possible.

"He's a great runner," Osborne said of Elston. "We had good pressure on him but he's strong enough and big enough to elude the pressure."

Even after that final touchdown, Osborne had one more trick left. On the ensuing kickoff, he tried a cross-field pass to set up a long return. But Houston's Tim Adams knocked down the desperate fling, the Cougars recovered and the game was over.

"There is no question in my mind that this football team is the best I've had in my 18 years," Yeoman said afterward. "Why? Because this team has played the toughest schedule and we've had the best record (12-1).

"This team was tougher and better in the big games. This team did what it had to do to win."