Facing a disastrous collapse that saw the Cardinals rally from down 7-0 to the lead in the 10th, Dukes took a 2-2 fastball from Cardinals closer Ryan Franklin deep over the center-field fence. The home run capped off a career night for Dukes, who tallied four hits for the first time in a single game in his career and notched his first home run of the season.
The Cardinals had taken the lead in the 10th on a Joe Mather home run when the Nationals stepped in for their turn in the extra frame. Cristian Guzman led off with a single before Dukes ended the game.
"I was just real intense today anyway," Dukes said after the game. "It was a good ballgame, just blow for blow."
Like many Washington hitters, Dukes had been struggling coming into the game. He had no home runs and was hitting just .155. But manager Manny Acta moved Dukes up from the No. 8 spot in the lineup to the No. 2 spot for both games Thursday, hoping he would see better pitches. Acta and Dukes agreed that the move paid off.
"It's only been two games, but the fact that he's gotten good wood on the ball so far, whatever works," Acta said after the game. "If he's happy there and continues to produce, that's what we're gonna do."
Dukes said it wasn't just the switch but also extra work in the batting cages to become more patient and comfortable hitting breaking balls, something Acta said he noticed. Dukes said he's been patient through his struggles this year, and it paid off tonight.
"I've just been putting in the work lately," Dukes said, adding that his coaches have been helping him immensely in the cages. "If [my coaches] want me to get in there, I've gotta want to get in that cage myself, and it's starting to work out for me."
St. Louis drove starter Tim Redding from the game after the veteran right-hander surrendered six runs in just 5 1/3 innings of work. The Nationals' bullpen held the score at 8-6 through the next 3 2/3 innings.
Closer Jon Rauch had the Cardinals down to one final out after striking out the pinch-hitting Albert Pujols. But the Cardinals rallied with two outs, scoring two runs and tying the game at 8.
The Nationals lit up the scoreboard early, matching their offensive output from the last two games with two runs in the first inning. They kept the hit parade afloat an inning later, taking advantage of a two-out error to extend the inning and plate three more runs. They added another two the next inning with some small ball, bringing the score to a comfortable 7-0. But that lead wouldn't last.
The Cardinals pulled back in the fourth, starting with a Troy Glaus solo home run in the fourth. They then strung two singles and a double together to draw within 7-3.
The Nationals answered with another run in the fourth after Boone doubled and scored on a Ryan Langerhans single to stretch the lead to 8-3.
The Cardinals roped the game back in in the top of the sixth, when relief pitcher Mark Worrell notched his first career hit and home run with two on, bringing the score to 8-6 and forcing Redding out of the game.
A loss Thursday night would have been especially painful for Washington after losing Game 1 of the doubleheader Thursday afternoon. A loss in the nightcap would have meant getting swept at home.
In Game 1, John Lannan threw six innings of two-run baseball, but the Nationals' offense was shut down in a 4-1 loss.
Dukes wasn't the only National to find offensive success Thursday night.
Outfielder/third baseman Kory Casto -- recalled from Triple-A Columbus just days ago -- has struggled mightily in his past Major League experience. But since returning to the big club, Casto has gone 5-for-9, including a 3-for-4 night on Thursday. Casto has also shown patience at the plate, drawing three walks in addition to his hits, notching his on-base percentage at .667.
Acta said after the game he thinks Casto is more relaxed at the plate than he was in his previous stints with the team. He said the Salem, Ore., native's approach at the plate has led to quality at-bats and offensive success.
"His first trip up here, it was real bad weather and he was trying to impress everybody," Acta said. "He looks a little bit more relaxed at the plate, and he's got the ability to have pretty good at-bats for us."
But Thursday night belonged to Dukes, the young right fielder with a cannon arm and plenty of potential. He flashed a toothy grin when asked if he knew he'd hit a home run when the ball left his bat in the 10th, nodding.
"Right away, I was just like 'I got them,'" Dukes said with a laugh. "And it felt good."
Zachary Osterman is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.