Nos. 1, 2 Upset on the Road : College basketball: Duke’s unbeaten streak ends at 23. Oklahoma State also falls.

On a night when six teams in the top 25 were beaten, top-ranked Duke and second-ranked Oklahoma State were among the unlikely victims--leaving major college basketball without an undefeated team.

Derrick Phelps made two free throws with 44.5 seconds remaining Wednesday night, giving ninth-ranked North Carolina a 75-73 victory over top-ranked Duke at Chapel Hill, N.C.

Second-ranked Oklahoma State also fell, 85-69, to Nebraska at Lincoln.

The Tar Heels brought an end to the nation’s longest winning streak at 23 games. North Carolina also snapped Duke’s Atlantic Coast Conference regular-season winning streak at 11 games.

“I just wanted to take my time and make the free throws, even though I missed one earlier,” Phelps said.

Instead of Duke (17-1, 8-1 in ACC play) taking control with one of its typical scoring runs, it was the Tar Heels (16-3, 6-2) who opened the second half with 10 consecutive points. North Carolina didn’t make a field goal down the stretch, but stayed ahead by making 12 of 15 free throws in the last 9 1/2 minutes.

The Blue Devils missed their first four shots in the second half and committed five turnovers in five minutes before scoring.

“We’ve had some strange ones with Duke here and some over there,” North Carolina Coach Dean Smith said. “But they’re going to be there at the end. You know that.”

After Phelps broke a 73-73 tie, Duke got the ball to Christian Laettner, who missed a shot over Eric Montross with 24 seconds left. The Blue Devils got the rebound, but Laettner missed again in the final seconds and Phelps came away with the rebound, dribbling into the corner and preserving the victory.

“They did a very good job of not even letting me catch it,” said Laettner of the Carolina defense. Normally a 64% field goal shooter, Laettner made just four of 11 shots.

“The second from the last shot was the easiest shot I took all night. Everybody thought I was going to take a three, then someone flew at me, so I had to do something else.”

Montross sat out two portions of the game, once to have a gash on the back of his head closed and in the second half for a cut under his left eye.

“I’m basically tired of them and I’m glad we got rid of them,” Montross said.

Hubert Davis scored 16 points for North Carolina, Montross and Kevin Salvadori had 12 each and Brian Reese added 10.

Nebraska 85, No. 2 Oklahoma State 69--Sophomore Jamar Johnson scored a career-high 25 points for the Cornhuskers in a Big Eight Conference game at Lincoln, Neb.

The Cowboys (20-1, 4-1) made only 37.9% of their shots and trailed throughout the second half.

Nebraska (15-4, 3-3) used a variety of zone defenses to frustrate Oklahoma State’s leading scorer, Byron Houston, who scored only four of his 15 points in the second half. Darwin Alexander had 16 points for the Cowboys.

The Cornhuskers iced the victory by making 21 of 25 free throws as Oklahoma State fouled repeatedly in a frantic effort to catch up.

Tennessee 83, No. 5 Arkansas 81--Allan Houston scored the winning basket with 43 seconds left and blocked a three-point attempt with 10 seconds to go to lift the Volunteers (13-7, 5-3) in a Southeastern Conference game at Knoxville.

Arkansas (17-4, 6-2) inbounded the ball under its own basket with 16 seconds left and Houston blocked Todd Day’s three-point shot. Robert Shepherd retrieved the ball for the Razorbacks but missed a 12-footer and Day’s tip wouldn’t fall in the final second.

Houston had 26 points for Tennessee, as did Lang Wiseman, who at one point scored 17 Volunteer points in succession to help the Volunteers rally from a 12-point deficit in the first half.

No. 8 Ohio State 86, Wisconsin 72--Chris Jent scored 27 points and Jim Jackson had 26 as the Buckeyes rallied from a seven-point deficit in the second half in a Big Ten Conference game at Columbus, Ohio.

The victory, Ohio State’s 29th in a row at St. John Arena, moved the Buckeyes (15-3, 7-1) back into a tie with Indiana for the conference lead.

Carlton McGee scored 20 points for Wisconsin (11-10, 2-6).

No. 12 Missouri 81, Iowa State 71--Jevon Crudup scored 19 points and Melvin Booker added 17 for the Tigers in a Big Eight game at Columbia, Mo.

Missouri (15-3, 3-2) had a 42-41 halftime lead but Iowa State (16-5, 2-3) took a 60-59 lead with 10:10 left on a basket by Justus Thigpen, who had 23 points.

The Tigers took command with a 18-4 run, sparked by two three-pointers and a basket by Booker.

No. 15 Michigan 81, Northwestern 58--The Wolverines beat the Wildcats for the 15th consecutive time in a Big Ten game at Ann Arbor, Mich.

Jalen Rose scored 12 of his 14 points early in the second half as Michigan (13-5, 5-4) pulled away from a 24-23 halftime lead.

Northwestern (8-11, 1-8), coming off a 46-43 upset of Illinois on Saturday, was attempting to win consecutive Big Ten games for the first time since the 1983-84 season.

No. 18 Alabama 74, Texas A&M; 61--Latrell Sprewell scored 18 of his 24 points in the second half and the Crimson Tide handed the Aggies their 10th consecutive loss in a nonconference game at College Station, Tex.

Texas A&M; (3-14) surprised the Crimson Tide (18-4) by taking a 29-27 lead on a dunk by Tony McGinnis with two seconds left in the first half and scored the first two baskets of the second half before Alabama rallied behind Sprewell.

Colorado 70, No. 21 Oklahoma 68--Donnie Boyce made two free throws with 12 seconds left in overtime to lift the Buffaloes to a Big Eight victory at Boulder, Colo. Colorado (10-8, 1-4) had lost 24 consecutive games to Oklahoma (14-5, 2-4).

No. 22 LSU 70, Florida 50--Shaquille O’Neal had 23 points, 15 rebounds and blocked six shots to lead the Tigers in an SEC game at Gainesville, Fla.

O’Neal, a 7-foot-1 center, controlled the game from the outset, drawing 14 of the 18 fouls called against Florida (10-9, 3-5).

LSU (14-4, 7-1) had only a 42-38 lead with 15:37 left, but the Tigers went on a 10-4 run and closed the game with a 15-2 burst.

Maryland 93, No. 23 Florida State 85--Walt Williams scored 38 points, his seventh consecutive ACC game with more than 30, and the Terrapins surprised the Seminoles at Tallahassee, Fla.

Florida State (14-6, 6-4) took its final lead, 48-47, on Andre Reid’s only basket of the game in the opening minute of the second half.

Maryland (9-10, 2-7) regained control and led by 10 points on three occasions in the final half, surviving Florida State’s last run of the night, an 8-0 spurt that brought the Seminoles to within 84-82 with 3:57 left.

Clemson 95, No. 24 Georgia Tech 78--Andre Bovain scored 20 of his 22 points in the second half and overtime to lead the Tigers in an ACC game at Clemson, S.C.

The Tigers (12-6, 2-5) outscored the Yellow Jackets, 24-7, in overtime, coming within one point of the NCAA record for points scored in an extra period, when they scored on every possession.

Georgia Tech (15-7, 3-5) lost its fourth ACC game in a row.