Jon Lipsitz, her head coach, planned to start Kayla Price in goal and bring in King for the second half against U of L. Less than four minutes into the game, King was on the sideline cheering on Price and the Wildcats when everything was thrown into chaos.
Price charged a ball played high into the box, jumping and colliding head-to-head with U of L's Irene Young. Immediately, it was clear Price was hurt and bleeding. Trainers raced to Price, who remained on the ground for a few minutes before coming to the sideline.
Price was clearly out for the game and King had to step up in a moment no teammate ever wants to face.
"When I saw KP go down, my heart broke for her," King said. "That's not a situation I want to come into."
After staying on the sideline briefly, Price was taken to the hospital, where she was treated for a cut that would need stitches and a tooth that was knocked out. King's thoughts were with Price - who is alert and in good spirits - but for the next two hours, there was a game to be played, and a big one at that. It's difficult to imagine King playing much better than she did.
King led the Cats (5-0-0) to a 2-0 upset of the 12th-ranked Cardinals, keeping the clean sheet that Price started. She was UK's anchor at the back, making six saves and stymieing a U of L attack that scored seven goals in two matches last weekend.
"It was just so much fun," King said. "After the initial shakes and jitters and rush that comes with that sort of situation, it was just fun. My team kept me in it and they kept me focused."
In her first two seasons as a Wildcat, King was a backup. In 2011, she saw only limited action behind Price, who started as a freshman. But heading into this season, King played her way into a time share at keeper. Through four games, she didn't allow a goal. That streak continued on Friday night.
"We talk about how you never know who is going to be the one," Lipsitz said. "You look at someone like Kayla King who got herself fit and had to make a decision who she wanted to be. She made a decision to be a great soccer player."
Her fitness and her improvement were tested in almost every conceivable way against the Cardinals. Into the 60th minute, King kept her team in a scoreless tie as the Cats' troubles with converting chances into goals continued. Finally, Natalie Horner headed in a Danielle Krohn corner to give UK a tenuous 1-0 lead. Just under 20 minutes later, it appeared that advantage was certain to disappear.
The referee whistled Kentucky for a foul inside its own box and Louisville was awarded a potentially game-tying penalty kick. Before Charlyn Corral stepped up to take the shot, King dropped to a knee to say a prayer and focus on the guidance of her coach.
"Jon says, 'Just react,' " King said. "That's the attitude I had going into it. I was fortunate enough that she didn't hit it upper 90 or to the other side. Luck, a big help from the Big Man and the coaches allowed me to make that save."
In an instant, King dove to her left, stretched and, not only made the save, but held onto the ball. Two teammates rushed to celebrate with her, but King brushed them aside; she had an attack to start. Within moments of the save, Arin Gilliland found Kelli Hubly from 35 yards out. The freshman found the back of the net for the first goal of her UK career.
"After a PK, as much as you want to be like, 'Yeah, this is awesome, woo hoo!' you can't lose your focus, especially against Louisville," King said. "They're a fantastic team. If we could use that emotion and go score a goal like we did, then fantastic. Then I'll give everyone hugs."
There was plenty of time for hugs when the final whistle sounded.
Entering the annual matchup with Louisville - the young Wildcats' first road game - Lipsitz said, win or lose, he was looking forward to learning about his team. He got more information than even he was bargaining for.
"I learned that we have an incredible amount of passion," UK head coach Jon Lipsitz said. "Not just for the game of soccer, who we want to be on the field, but for one another. We had a player seriously injured five minutes into the game and there are a lot of teams, that when that happens, they shut down out of fear or out of worry. They didn't do that."
Even if they had wanted to, the hundreds of Kentucky fans that had invaded Cardinal Park may not have let them. The goal that King stepped into when she came in for Price was surrounded by a boisterous group of Wildcat faithful who had boarded a pair of buses commissioned by the athletic department to make the drive from Lexington.
"When I came in, it was a rush of emotions to say the least," King said. "What actually calmed me down was the Big Blue Nation right behind me cheering for me and drowning out the Cardinal fans."
Without all the UK fans, it's unlikely that U of L would have set a school record with an attendance of 3,520 on Friday.
"I hope that everybody in Big Blue Nation understands what they did for us tonight," Lipsitz said. "I want to say thank you to the department for getting t-shirts and buses. We felt that the whole time. We always say, 'Blue got in.' I think that's a phrase. Let me tell you, Blue got in."
Among those blue-clad fans were King's mother, stepfather, both of her sisters and numerous friends from Manual High School, including her best friend - a U of L student - who wore blue body paint with King's name and her No. 33 on the back.
The way Price entered the game may have been something she'd rather forget, but the way she left the field is something she'll never want to.
"It's really special to come home and have my team play so well under the lights on a Friday night against our archrival," King said.