OMAHA, Neb. — The way its regular season unfolded, a national championship for Oklahoma would have seemed impossible.The way the postseason unfolded, well, there was no stopping the Sooners.OU completed the improbable run to its first national championship since 1994 with a 13-2 victory over North Carolina in the winner-take-all Game 3 of the College World Series finals Monday night, a performance that featured the prodigious offensive production and clutch pitching the Sooners rode through the NCAA Tournament.“I think we knew the talent was always in the room,” said Jaxon Willits, named the CWS most outstanding player. “We got hot at the right time, and now we’re national champions.”The Sooners (43-23) won the Southeastern Conference’s seventh straight title, quite an accomplishment for a team picked 14th in the 16-team conference in the preseason, finished 11th and entered the postseason off losses in seven of nine games.To get to Omaha, they beat No. 2 national seed Georgia Tech twice on the road in regionals and swept upstart Kansas on the road in super regionals. To get to the finals, they beat No. 3 Georgia twice in bracket play.“They got really confident the last month,” OU coach Skip Johnson said. “They care about each other. They didn’t want to give in. They were selfless.”North Carolina (54-14-1) was runner-up for the third time since 2006 and now has 13 CWS appearances without a title. Only Florida State, with 24, has more without winning it all.The Sooners were back in top form offensively after managing only four singles in a 6-2 loss in Game 2 and handed the Tar Heels the …