STATE COLLEGE, Pa. (AP) As games wear on, Saquon Barkley can sense when defenders want no part of him.
Hands resting on hips is a good indicator. Labored breathing at the bottom of piles is another that Penn State's offense has opponents on their heels.
Such was the case Saturday in Penn State's 41-14 win over Iowa. It has been a trend in the middle of the season for the No. 12 Nittany Lions (7-2, 5-1 Big Ten, No. 12 CFP). They've developed a killer instinct and offensive coordinator Joe Moorhead's offense is putting teams away emphatically.
''You can kind of see it in the defense's demeanor when you're gashing them,'' Barkley said. ''Coach Moorhead instills in the offense to have that killer mentality. To finish them.''
Penn State's longest conference winning streak since 2011 has been fueled by an offense that is taking advantage of late turnovers and is powering through defensive fronts with a two-headed rushing attack that also features quarterback Trace McSorley whose completion percentage is at its best over the final 15 minutes.
''That's something that we kind of pride ourselves on - not too heavily relying on one thing,'' wide receiver Chris Godwin said. ''We work really hard in practice to come out and prove that and I think we did a great job of doing so.''
The Nittany Lions are averaging 41.2 points per game over their last four and are scoring more than half of those points in the final two quarters. They've added 21 points off of three fourth-quarter turnovers during the winning streak in which their offensive line is moving the line of scrimmage.
Not counting kneel downs, Penn State is averaging 135 yards in each of its last four fourth quarters and has shredded defenses with seven plays of 20-plus yards in that span.
Barkley's sensational skill set has been a major factor. The sophomore back has scored on long plays to begin each of the last two fourth quarters. A 44-yard reception against the Hawkeyes was the latest deflator and he turned in an 81-yard run through an exhausted Purdue defense two weeks ago.
''Our offensive line is doing a great job at the line of scrimmage,'' Godwin said. ''As the game starts to wear down, they start to put more and more pressure on teams. You can kind of sense that they just want to get it over with.''
Slow starts that dogged the Nittany Lions early in the season also taught them a valuable lesson.
''We know how it is to be a second-half team, how to be able to be down and come back in the games that were over, so when you get the chance and you're up early, you've got to step on the pedal and finish them.''
Although Moorhead's offense is typically described as ''up-tempo,'' Penn State actually uses a good portion of the play clock rather than rush from snap to snap. The Nittany Lions never huddle, however, and do require players to get set quickly so they have time to look to the sideline for Moorhead's play calls after he's surveyed the defense.
An offseason dedicated to nutrition helped offensive linemen replace fat with lean muscle in order to handle the rigors of such an offense in which they spend more time in their stances.
''We can play with any defense,'' offensive guard Ryan Bates said. ''We're more conditioned than any defense that we play because we've got so much practice and so much conditioning in this offense. We've come a long way and we're getting pretty close to perfecting it.''
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