With runners on first and second base and no outs, Valencia bobbled a ground ball from Jhonny Peralta that should have been a routine forceout at third base, and likely would have been a double play.
Instead, Tigers third baseman Brandon Inge went on to line an RBI single to right field off Randy Flores to push Detroit past Minnesota, 11-10, in the 13th inning of a four-hour and 19-minute marathon game at Comerica Park.
"It was a play that needs to be made, and I didn't make it," Valencia said. "Obviously, it's a big play. From there, we are at least getting an out at third and possibly even turning a double play. It's tough when it works like that, but that's how baseball is."
It's hard to call Valencia the goat on the night. After all, he recorded his second career grand slam in the first inning and followed up with a solo homer in the fifth. It marked the first multi-homer game of his career.
If that wasn't enough, Valencia had a chance to be the game-winning hero in the top of the 13th inning. He stepped to the plate with two outs and the bases loaded, but struck out swinging vs. Tigers rookie Daniel Schlereth (1-0).
"We got off to a good start and the offense looked great the whole game," Valencia said. "We came into situations at the end, myself included, and we couldn't get the job done at the end when we were playing extra innings. We scored a lot of runs, and it came down to defense and I didn't really help that. The timely hitting at the end didn't really help us."
The first five innings of the game seemed like a batting-practice session for both teams. After Jason Kubel drove in a run to start the first inning, Valencia bombed a grand slam off Tigers starter Jeremy Bonderman to give the Twins a big five-spot in the first inning.
Surprisingly, that wasn't enough run support for Twins starter Carl Pavano, who had owned the Tigers in his career. Entering the game, he was 5-2 against Detroit in eight career starts, with a 2.97 ERA.
Pavano gave up single runs in the first and second innings before the game slipped away in the fourth. He surrendered three home runs in the frame, resulting in the Tigers posting a five-spot of their own and erasing the right-hander's cushion.
"I just didn't set the right tone," Pavano said. "I got a five-spot in the first inning. How many times do you get that? Then you go out there and give it up. It's embarrassing. My job as a starting pitcher is to set the tone and go out there and get outs, especially with a five-run lead. I basically pitched poorly.
"Then that one inning got ahead of me. They hit three home runs. That's ridiculous."
Kubel and Valencia hit back-to-back homers in the fifth inning to chase Bonderman on a sour note in what may have been his last start at Comerica Park, as he'll be a free agent at the end of the season.
The offense didn't stop there in the fifth for the Twins. They tacked on yet another five-spot to take a three-run lead. But that lead quickly vanished, again when Detroit scored a pair of runs in the bottom of the fifth inning and tied the game in the seventh.
After the offensive outpouring that saw both teams combine for 20 runs through seven, the game took a 180-degree turn. It turned into a pitching duel. More like a battle of the bullpens.
Of the nine pitchers the Twins used on the night, five didn't allow an earned run. The Tigers did equally well, with five of their seven pitchers also posting zeroes.
"It was a crazy game tonight, obviously," said third-base coach Scott Ullger, who filled in for Ron Gardenhire. The Twins skipper was accidentally hit by a ball in batting practice and had impromptu surgery on his ear in the clubhouse to relieve pressure. However, Gardenhire said he likely will be able to return for the series finale Sunday afternoon.
"We came in and scored 10 runs and ended up having to hold on then lose it," Ullger added. "That was very surprising. Obviously, neither team pitched good in the beginning or the middle. In the end, both teams pitched pretty good. Crazy plays happened. Some guys had big nights offensively. We just came out on the short end."
The first real offensive threat for either team after the seventh inning came in the 13th when the Twins loaded the bases with one out. But Schlereth struck out Kubel and Valencia to end the threat and keep the Tigers alive for their walk-off win in the 13th inning.
"It's one of those games both teams fought their tails off," Tigers manager Jim Leyland said. "They got it clinched and we can't win it, so you would think maybe they just didn't go at it hard. That's unbelievable. Both teams went at it like that was a playoff game, I thought."
For Pavano and the Twins, it was a game that slipped away. In the first two games of the series, Minnesota gave up a combined 21 runs. More alarming, the runs were racked up in starts by Francisco Liriano and Pavano, who are slated to start Games 1 and 2 for the Twins in the playoffs.
"They hit good pitches and they hit bad pitches," Pavano said. "I looked at the tape and a lot of my pitches were up over the plate. But those things happen. It's disappointing to me. I was the first pitcher out there. We used almost our whole bullpen. We played 13 innings and got a loss. That's definitely on me. I'm disappointed about it."
Alex DiFilippo is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.