Kristian Doolittle scored three straight key baskets late in overtime, and Oklahoma defeated Northwestern 76-69 on Friday night for its seventh straight win.
Doolittle, who finished with a team-leading 14 points, connected on layups 50 seconds apart, then added a close-in jumper with 19 seconds left in overtime to make it 74-69. Miles Reynolds sealed it with layup with three seconds remaining.
Christian James had 12 points and nine rebounds and Rashard Odomes aded 13 points -- all in the first half -- to help the Sooners (11-1) prevail in a physical non-conference match-up of Power Five schools.
Vic Law led Northwestern with 23 points and eight rebounds. Dererk Pardon had 15 points and seven rebounds, while Ryan Taylor had 14 points as Northwestern (8-4) fell short in its biggest challenge before resuming Big Ten play next month.
Northwestern was hindered by sour free-throw shooting, connecting on only 34.8 percent of its shots (8 for 23) from the line,
Neither team could sustain great shooting from the floor in a tightly played contest. Oklahoma shot 42.7 percent and Northwestern shot 42.4 percent.
With the score tied at 66, both teams missed chances in the final minute to win it.
As he tried to drive in for a layup, Oklahoma's Aaron Calixte was stripped off the ball by Pardon. Northwestern came back down for a winning shot, but Taylor's 3-point attempt from the left side with 4.2 seconds caromed off the rim.
Oklahoma's only loss is to another Big Ten opponent. Wisconsin beat the Sooners 78-58 at Norman, Oklahoma on Nov. 22.
The game was tied 32-all after a rugged first half defined by two big swings.
Oklahoma came out shooting cold, and Northwestern pulled ahead 19-8 by 9:06 using balanced scoring for a 13-2 run.
Then it was the Sooners' turn. Oklahoma went on an 18-6 roll behind Odomes, who led all scorers with 13 points in the first half.
The Sooners took their first lead, 26-25, when Doolittle hit a jumper from inside the paint. Then the two teams tussled until the break.
Oklahoma pulled out to a 48-42 lead 6:17 into the second half. Northwestern came back with an 11-2 run capped by Taylor's 3-pointer from the top of the key with 8:19 left that put the Wildcats ahead 53-50.
That set up a tight back-and-forth tussle down the stretch. Pardon's put-back dunk with 1:17 to go tied it at 66.
Oklahoma won the only previous meeting between the two programs last year in Norman, 104-78.
Oklahoma: The Sooners entered the week one spot outside of the AP Top 25, and they strengthened their resume with a wins over Creighton and Northwestern . Oklahoma also has wins over Florida, Notre Dame, Wichita State and USC.
Northwestern: The Wildcats had their hands full with a top Big Five opponent after rolling past DePaul and Chicago State, a pair of local non-conference opponents, in their previous two games.
Oklahoma closed out its non-conference schedule. The Sooners are off until they begin Big 12 play on Jan. 2 at No. 1 Kansas.
Northwestern has one more non-conference game, against Columbia on Dec. 30, before resuming its Big Ten schedule at Michigan State on Jan. 2. The Wildcats are 0-2 in conference play, having dropped 2-point decisions at Indiana and to No. 5 Michigan earlier this month.