OKLAHOMA CITY -- If ever the term “down, but not out” applied, it was Monday night at ASA Hall of Fame Stadium.

For three and a half hours, Oklahoma’s Keilani Ricketts and Tennessee’s Ellen Renfroe matched each other almost pitch-for-pitch in the opener of the best-of-three championship series to determine the winner of the 2013 Women’s College World Series.

It appeared Renfroe had won the opening round after teammate Madison Shipman launched a Ricketts pitch into the center field seats with two runners aboard in the top of the 11th inning.

However, down to their last strike – twice – the Sooners found a way to keep the evening going.

An RBI-double by Brittany Williams gave OU life after a dropped wind-aided pop fly put a runner on base, cutting the margin to 3-1. With two strikes on the board, Destinee Martinez lined a triple over UT center fielder Tory Lewis’ head to score Williams and cut the deficit to one.

Again, with two strikes shining brightly on the center field scoreboard, Callie Parsons lined a shot into the outfield. When the dust settled, a run had scored and Parsons was thrown out at third base.

The damage was done, however, and somehow the Sooners had forced another inning.

Ricketts and Lauren Chamberlain took advantage, as Ricketts shut down the Volunteers in the 12th inning and Chamberlain, in a fitting, dramatic end, launched a moon shot just inside the left field foul pole to give OU a 5-3 win and a 1-0 series lead.

“I don’t even know where to start,” OU head coach Patty Gasso said. “Except for that was the best game I have ever been a part of. Both teams just battled. Both pitchers were exceptional.

“I don’t remember it right now but I will never forget it, if that makes any sense.”

The 2013 WCWS has provided plenty of drama already. Thunderstorms rolled through Oklahoma City last Friday, forcing the evacuation of most teams from their hotels and the postponement of the scheduled games. A day later, Florida and Nebraska played a game for the ages, going 15 innings and forcing the final game of the day, Arizona State and Michigan, to play into the early-morning hours of Sunday.

But nothing can top Monday’s contest.

“This is the championship series, it is supposed to be a game like that,” said Chamberlain, who now has 30 home runs this season.

“The pitching performance out of both Keilani [Ricketts] and Ellen [Renfroe] was unbelievable,” UT co-head coach Ralph Weekly said. “Both of them pitched phenomenal games. All we can do is congratulate Oklahoma … that is all you can do after a game like this.”

Ricketts delivered 188 pitches through her 12 innings in the circle. She struck out 13, walked six and gave just five hits – only two of the hits came prior to the ninth inning.

Renfroe tossed 180 pitches. She struck out 13 and walked just three.

“[Co-head coach] Karen [Weekly] and Ralph talked to us in the postgame about how you are going to get knocked down,” Renfroe said. “You can get knocked down, but it is about how you get back up and bounce back. We are just going to come out fighting again [Tuesday].”

“Nobody likes to lose, it’s a rough loss,” Shipman said. “It is a quick turnaround, so we can’t dwell on it.”

UT senior third baseman Raven Chavanne summed it up by saying, “flush it, it’s in the past, [Tuesday] is a brand new day.”

Entering the 2013 Women’s College World Series, most conversations concerning the nation’s top pitchers included Ricketts, Blaire Luna and Dallas Escobedo. Renfroe proved she belongs on that list.

On Monday night, the junior from Jackson, Tenn., faced the daunting task of shutting down one of college softball’s most feared lineups – the Oklahoma Sooners.

Entering the opener of the best-of-three championship series, the Sooners were averaging more than eight runs per game in the 2013 NCAA tournament. Five times in eight starts, the OU offense did not need the full seven innings. In the three WCWS games played by OU, they had outscored opponents 23-5; opposing pitchers had issued 17 walks.

While OU bats were lighting up one side of the bracket, Renfroe was shutting down those on the other side. In 33 innings of work, she had struck out 42 and allowed five earned runs. She shutout Washington, held Florida to two runs and relieved older sister Ivy in the win against Texas on Sunday.

Time and again, Renfroe worked out of jams.

Getting out of the bottom of the ninth will not soon be forgotten by the Rocky Top clan. With two runners on base and nobody out, Renfroe struck out Ricketts. A wild pitch and base on balls later, the bases were loaded with just one out.

Renfroe got Jessica Shultz to hit a slow roller to first where Melissa Brown fielded and threw home to get a sliding runner. Martinez then struck out and the Tennessee faithful erupted.

But in the end, OU’s solid top-to-bottom lineup, found a way to rally when it counted.

“There is no let-up in their lineup,” Renfroe said. “As soon as you get one of them out, you take a deep breath and get ready for the next one.”

Coaches, players and fans will take a deep breath and try to get ready for the next one.

Oklahoma and Tennessee meet again Tuesday at 8 p.m. ET. A Sooner win and they are national champions; a Volunteer victory means a third game on Wednesday.