NORMAN — Both Oklahoma and Tennessee knew the drill coming into Sunday's rubber game. With the series on the line, it would be an old-fashioned pitching duel between Sam Landry and Karlyn Pickens.

For a brief moment, it looked like the Landry and the Sooners would emerge victorious.

After the Sooners' offense was non-existent through the first two innings, they started quickly in the third inning. Hannah Coor hit a leadoff single then stole second. Abby Dayton then followed with a single and then stole second. Nelly McEnroe-Marinas forced a walk to load the bases.

Kasidi Pickering stepped to the plate and delivered an RBI double that cleared the bases, giving the Sooners a 3-0 lead. In a series where both offenses struggled, it felt like all the momentum OU would need.

Instead, the Volunteers responded. Landry got two quick outs to open the frame, but Tennessee kept battling. Two walks and a single loaded the bases, then an RBI double from Laura Mealer cut OU's lead to 3-2.

On the next at-bat, Ella Dodge smoked a three-run home run to right field to complete the two-out rally.

In a dramatic turn of events, OU's three-run lead turned into a two-run deficit. The Sooners (31-3, 9-3 SEC) never recovered from that momentum change, as they fell 5-3 to Tennessee.

"That’s a World Series team we just played and they’ve got an elite, elite pitcher," OU coach Patty Gasso said. "... We’re making contact, it’s just not going anywhere. And I felt like we were kind of trying to make contact versus swinging like (Pickering) has been swinging and just really trying to square the ball up. Pickering had a phenomenal weekend off of her and it’s a good example of tenacity and focus, but planning.

"And our team learned that we have to walk up with a plan to execute."

The loss marks the Sooners' first series defeat in conference play. They lost on Friday 5-2 and won 4-1 on Saturday.

Landry eventually bounced back from that rough fourth inning, retiring nine of the final 10 batters she faced.

But the Sooners' offense looked shellshocked as Pickens kept them from finding any rhythm. The Sooners had 12 of their final 14 batters retired over the final four innings, as the only hit came on a single from Abby Dayton with two outs on the board in the seventh inninmg.

But Nelly McEnroe-Marinas followed that with a strikeout, ending the game.

Landry finished with four hits and five runs allowed while striking out six and walking two. Pickens struck out six and allowed three hits, three runs and three walks.

It's just the third loss of the season for the Sooners. But it's their third loss in five conference games, and it's their first series loss of the season. The sky isn't falling, but Gasso knows there's a lot of work to do.

"So we understand this felt really uncomfortable," Gasso said. "It did not feel good watching this happen on our own field. But this is what this young team has to learn. As we go forward, it’s going to happen."

— If it wasn't Pickering, offense was really tough to come by this weekend, particularly on Saturday and Sunday. In Games 2 and 3, Pickering went 4-for-5 at the plate. The rest of the team combined for five hits.

For the weekend, Pickering was sensational. She finished 7-for-8 at the plate with two walks.

"One thing in the game I try to talk to everyone, is we just have to be better," Pickering said. "Everyone needs to be better. Nobody up there is hitting the home run... Everyone has an opportunity to be better. And just knowing that Karlyn is good. I'll give that to her. She's amazing. But we trained all week for this. We should've executed better. We just have to be better moving forward."

— Gasso on Landry's slip-up in the fourth inning: "She threw one first pitch to a hitter, threw a change up, and she had a plan to say, ‘It's a change up, I'm sitting on it.’ And she hit it out. And that was kind of the result of all of this. Ended up like a walk and then hit, and then we got to that situation."

— Three of the Sooners’ four hits came in the third inning. The Sooners 2-for-12 with runners on base and 2-for-7 with runners in scoring position.

— It was a rough weekend for Gabbie Garcia, who went 1-for-8 across the three games. She finished 0-for-3 on Sunday.

— The struggles continue for Parker, who went 0-for-3 at the plate with zero walks. She's now 2-for-30 (.067) at the plate in conference play.

— Up next: The Sooners will look to bounce back at UT-Arlington on Tuesday (6 p.m.)

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