NORMAN, Okla. — Jake Opitz and Bryce Nimmo combined to drive in five runs, while Johnny Dorn pitched into the ninth for his sixth consecutive decision, leading Nebraska to a 6-4 victory over No. 23 Oklahoma in the nightcap of Saturday's double-header.

With the win, the Huskers (21-14, 6-8 Big 12) tied the series at 1-1 heading into Sunday's rubber match, which is set for 1 p.m. and will be carried across the state on the Husker Sports Radio Network. Oklahoma (25-12, 5-6 Big 12) won Saturday's first game, 3-0 behind a complete-game four-hit shutout from Stephen Porlier.

Opitz went 2-for-5 and drove in three runs, including a two-run, bases-loaded single in the top of sixth off of Sooner reliever Nich Conaway, while Nimmo had two hits, a pair of stolen bases and drove in a pair of runs, including a key fifth-inning RBI single after Oklahoma to a 3-2 lead.   The Huskers scored five of their six runs in two-out situations in the nightcap, a factor that played a major role in getting the split on Saturday.

"We did a great job with our two-out hitting tonight," Nebraska coach Mike Anderson said. "I thought Nimmo has been swinging well, Andy Gerch did a good job and Jake Opitz had a really big at-bat against one of their best guys."

With the score tied at three, Nebraska took advantage of some wildness by the Sooner bullpen, as relievers Danny Grande and Conaway combined to walk the bases loaded, highlighted by a Tezak's 13-pitch walk from Conaway after being down 0-2. Two batters later, Opitz gave the Huskers the lead for good, sending  Conaway's 1-0 offering to center for a two-run single.

While the Huskers, who totaled 12 hits, relied on timely hitting, Dorn turned in his usual solid effort. The junior scattered six hits over 8.1 innings to up his record to 6-1 on the season. Dorn, who now has 27 career wins, struck out a pair and walked only one before Matt Foust got the final two outs to record his third save in as many chances.

"I thought we got two great performances from our starting pitchers today, performances that should get us wins," Anderson said.  Johnny was very good tonight. He didn't have his best stuff, but located well."

The Huskers got on the board in the top of the second inning against Oklahoma starter Heath Taylor on Nimmo's RBI single. Craig Corriston tripled into the corner and scored moments later, as Nimmo slapped a single into right.

Nebraska extended its lead to 2-0 one inning later on a run-scoring single from Opitz. Andrew Brown, who extended his hit streak to 14 games, opened the frame with a single and moved to second on Jeff Tezak's sacrifice bunt before Opitz sent a 1-0 offering to center to give NU a two-run cushion.

The Sooners rallied back, scoring once in the third and taking advantage of a pair of Husker errors to plate two unearned runs one inning later. In the third, Aaron Reza doubled and eventually scored on Aljay Davis' sacrifice fly to pull Oklahoma within 3-1. Reza went 2-for-4 and scored twice to lead OU in the nightcap.

Oklahoma took the lead for the first time with a pair of unearned runs against Dorn in the bottom of the fourth. After Aaron Baker opened the fourth with a triple, Dorn retired the next hitter and had Cory Williamson ground out to Brown at first, who fired to third to get Baker, who was hung up third and home. The Huskers could not take advantage, as Corriston was unable to field the ball cleanly, allowing Baker to score and Williamson to reach second on the play. The miscue proved costly, as Williamson stole third and subsequently on a throwing error from catcher Mitch Abeita.

The Huskers fought back in the top of the fifth against Taylor, knotting the score on Nimmo's second hit of the night, a RBI single to center. With two outs and Jake Opitz on first, pinch hitter Steve Edlefsen was hit by a pitch before Nimmo lined a 1-0 offering to center to score Opitz.

The Huskers tacked on an insurance run in the top of the seventh, as Nimmo opened the frame with a walk, stole second and eventually scored after a pair of two-out wild pitches from Conaway.

In the opener, Porlier struck out six without a walk and allowed only three Huskers to reach scoring position to improve his record to 5-3 on the season. Porlier's shutout marked the first time that Nebraska had been shutout in conference play since the 1998 season.

Porlier out-dueled Husker ace Tony Watson, who nearly tossed his second consecutive complete game in a losing effort. Watson, who dropped to 3-2 on the year, allowed 11 hits and struck out four while throwing 7.2 innings.

DJ Belfonte, Ryan Wehrle Andrew Brown and Jeff Tezak accounted for Nebraska's four hits, as both Brown and Tezak extended their hit streaks to 12 games apiece.

The two teams will wrap up the series Sunday afternoon at 1 p.m.