"I just focused on staying on his hip and making sure I recognized the set plays they were running for him," said Brooks, who spent much of the second half guarding Talor Battle.
The Temple guard held Battle, who came in averaging 20.1 points a game for Penn State, to eight points on just 3-for-15 shooting and 0-for-5 on 3-point attempts.
Brooks said his main objective was to slow down Battle.
"I believe our play on the defensive end translates into how we play on offense," he said. "Everything, for me, starts on defense."
Brooks shot 8-for-18 from the field and grabbed six rebounds. He was the only player to score in double figures for the Owls (6-2).
Brooks' jumper from the top of the key with 1:32 left in the game gave Temple a 43-40 lead. His two free throws with 11.6 seconds to go - after an offensive foul against the Nittany Lions - accounted for the final margin.
Chris Babb came off the bench to lead Penn State (5-3) with 11 points.
The Owls made just 18 of 60 shots (30 percent), while the Nittany Lions shot 15-for-43 (34.9 percent).
Penn had won four consecutive non-conference games on the road, including last season. They would have achieved a program-record fifth straight with a win on Saturday.
The Nittany Lions' last non-conference road loss had been a 79-67 setback at Saint Joseph's on Dec. 1, 2007.
Temple also had a 17-7 edge in offensive rebounds, with Lavoy Allen accounting for seven by himself. Allen finished with 12 rebounds total to go along with his eight points, two blocks and two assists.
"That's the game," Penn State coach Ed DeChellis said. "They won the game on the glass. We gave them 17 offensive rebounds, and that was the difference."
There were only five fouls called in the first half, which ended in a 22-22 tie, and neither team attempted a free throw until 10:13 remained in the second half.
"It was really strange," said Fran Dunphy, the Temple coach. After Brooks' jumper with 1:32 to play gave the Owls a 43-40 lead, Battle missed a layup for Penn State, only to have teammate David Jackson grab the rebound. Penn State's Bill Edwards was then fouled and converted both free throws to make it 43-42 with 57.1 seconds left.
Brooks then turned the ball over in the lane for Temple at the other end, and Penn State called a timeout.
Edwards, being guarded by Temple's Rahlir Jefferson, was then called for pushing off on Jefferson out near the left elbow with 14.7 seconds left.
On the inbound, Allen was trapped under his own basket when Jefferson, a freshman, called a timeout to avoid a turnover. The Owls then inbounded, and Brooks was fouled and made both free throws to stretch the lead back to three.
Battle had the ball on Penn State's final possession and slipped as he dribbled toward the right wing. The Nittany Lions never did get off a final shot.