Realizing that his outstanding performance the night before meant nothing now, Dukes told himself to look harder for the pitcher's release point.
"I dug down a little bit," he said. "I was a little tired basically."
Dukes hit a three-run double in the 14th inning to erase the fatigue of a long, sunny afternoon, helping the Washington Nationals beat the Atlanta Braves 7-4 on Sunday.
Dukes, who homered twice and went 4-for-5 in Saturday's 10-inning victory, was hitless in six at-bats before he faced Jeff Bennett in the 14th.
Bennett (2-6) gave up a leadoff walk to Anderson Hernandez, an infield single to Willie Harris and a one-out intentional walk to Lastings Milledge before Dukes doubled down the third-base line.
"I didn't start thinking until like the 10th inning," Dukes said. "That's when I realized, man, I was dying out there.... That's when you realize what kind of day it is."
Steven Shell (2-1) pitched the 12th and 13th innings, striking out two and giving up two hits.
Joel Hanrahan got two quick outs before pinch-hitter James Parr, a rookie pitcher, walked and moved to third on Yunel Escobar's double. Hanrahan retired Jeff Francoeur on a grounder to earn his eighth save in 11 chances.
The Braves have lost two straight and seven of 10. Manager Bobby Cox was disgusted with much of what he saw, including reliever Blaine Boyer's walk of rookie catcher Luke Montz in the eighth and Bennett's walk of Anderson Hernandez in the 14th.
Both baserunners eventually scored, Montz on rookie Alberto Gonzalez's two-run double and Hernandez on Dukes' double.
"Well, we walk a guy who never had a base hit in his career," Cox said of Montz. "And we walked the leadoff hitter in the last inning. We didn't come close."
Washington won the season series against Atlanta 12-6.
Gonzalez hit his first career homer and had three RBIs for the Nationals.
Milledge's 14th homer made it 1-0 in the second, but the Nationals' center fielder gave the lead back in the bottom half of the inning, losing Chipper Jones' fly ball in the sun and allowing two runs to score for a 3-1 Braves lead.
"I saw it the whole way in the air and then I got caught up in it," Milledge said. "It was just a bright day. No clouds."
After Gregor Blanco's RBI single tied the game at 1, Jones was credited with a double and two RBIs because Milledge's glove didn't touch the ball. Both runs were charged to Nationals starter Collin Balester, who left for a pinch-hitter in the seventh after giving up four runs and 11 hits.
The Nationals' bullpen backed him up, though, holding Atlanta scoreless for the final eight innings. Shell and Hanrahan were preceded by Charlie Manning, Jesus Colome, Garrett Mock, Mike Hinckley and Saul Rivera.
Atlanta starter Jo-Jo Reyes left after six innings with a 4-1 lead and looked as if he was going to snap his streak of six straight losses, but relievers Julian Tavarez and Boyer couldn't hold the lead.
Tavarez pitched the seventh, giving up Gonzalez's homer to make it 4-2. Boyer began the eighth, allowing Milledge's leadoff single and walking Montz before Gonzalez doubled to tie the game.
"I went back at looked at it again," Boyer said. "If I hit my spots, I've got an out. It just wasn't a good pitch. He beat it. It's the story of the season. I thought I got it on the outside corner, and I didn't."
Reyes, whose losing streak is Atlanta's longest since Marty Clary dropped eight straight in 1990, gave up a run and four hits The left-hander stranded four runners in scoring position, two of them with the bases loaded when Willie Harris popped up to end the fifth.
Notes: Jones went 3-for-6 to raise his average two points to.358, one point behind St. Louis' Albert Pujols, who leads the majors.... Nationals manager Manny Acta indicated that 1B Dmitri Young (diabetes) could come off the disabled list before Tuesday's game at New York.... Washington 3B Ryan Zimmerman went 0-for-7 after hitting safely in 12 straight games.... Francoeur, who grounded into double plays in the third and the 10th, popped up in the first to drop his average with the bases loaded to.138 in 28 at-bats this year.... Since June 17, the Nationals are 10-27 on the road.