CINCINNATI -- Washington closer Henry Rodriguez couldn't be touched Saturday night as he finished off a victory against Cincinnati. Sunday evening, Rodriguez couldn't find his command and it cost the Nationals a chance at their first three-game sweep of the season.
Rodriguez gave up a walk-off grand slam to Reds first baseman Joey Votto -- Votto's third home run of the game -- with two outs in the ninth inning, as Cincinnati salvaged the finale of the series with a 9-6 victory at Great American Ball Park. Rodriguez struck out all three batters he faced in the ninth inning Saturday in earning his eighth save of the season in a 2-1 victory, but he never got comfortable on a sloppy mound Sunday.
He walked Drew Stubbs and Chris Heisey in front of Votto, who finished the game with a career-high six RBIs. Rodriguez had gotten ahead of Heisey 0-2, but couldn't put him away. It was the third blown save of the season for Rodriguez in 11 opportunities.
"That's a tough loss," said Nationals manager Davey Johnson. "Rodriguez has done such a great job. You just can't walk guys like that. You don't want Votto up there ever. He walked the guys he should have gotten out. It was a tough night, the conditions and everything, but we gave them some cheap runs and you can't do that."
The loss drops the Nationals (21-13) one-half game behind Atlanta in the National League East. It was the sixth time this season the Nationals lost the final game of a series of three or more games when they had a chance to complete a sweep.
The game's start was delayed by rain for three hours, 36 minutes. This is the only scheduled trip into Cincinnati this season for the Nationals, so the umpires and stadium officials were willing to wait out the weather. Rain returned in the eighth inning and began making the mound conditions difficult.
The loss overshadowed the continued resurgence of second baseman Danny Espinosa, who had a pair of hits, including a two-run double in the fifth inning that gave the Nationals a 4-2 lead. Espinosa entered the series hitting just .191 with one home run and two RBIs, but went 5-for-11 with five RBIs and two home runs in the three games. Espinosa now has a five-game hitting streak.
The Nationals offense overall got a boost in Cincinnati. They scored a total of 15 runs in the series and had 16 hits on Sunday. The problem was that they left 14 runners on base.
"It's discouraging right now because we lost," said first baseman Adam LaRoche, who went 2-for-5 with a double and an RBI on Sunday. "Big picture, it's nice that the bats are coming alive a little bit."
Even with the loss, the Nationals still own their best record after 34 games since moving to D.C. in 2005. It is just the third time in those eight seasons they have had a winning record at this point of the season. The question they will face as the season progresses is how a young team that hasn't enjoyed much success in the past will handle the ups and downs -- like losing on a walk-off grand slam -- the baseball season always produces.
"It's just baseball, and I think we've done well, especially with the injuries that we've had, and people filling in roles until guys get back," said center fielder Rick Ankiel. "It's early, and there is so much baseball left that we just have to come out and play our game and then see where we're at down in September."
Votto hit solo home runs in the first and fourth innings off of Nationals starter Edwin Jackson to counter single runs Washington scored in the second and third innings. Jackson retired eight in a row in between Votto's home runs, but lasted just five innings, allowing three runs on five hits before being lifted for a pinch-hitter. It was just the third time in the last 20 games a Washington starter didn't produce a quality start.
The Nationals had a three-run lead, 6-3, heading into the bottom of the eighth inning. Chad Tracy produced his seventh pinch-hit RBI of the season in the seventh inning and LaRoche added an RBI single in the eighth.
The Reds were threatening in the bottom of the eighth with Stubbs on third and Votto on second, but reliever Sean Burnett struck out Brandon Phillips and induced Jay Bruce to hit an apparent lazy fly ball to right-center.
The only problem was that right fielder Bryce Harper never saw the ball because of the overcast skies. The lights had nothing to do Harper losing the ball, which fell well behind him and went to the wall for a two-run double that brought the Reds back to within one run, 6-5.
"I had no clue. I had no idea what happened," said Harper. "It sucks that it happened, but I had no clue where it was or where it was going. There was nothing I could do about it."
Rodriguez gave up a single to Reds catcher Ryan Hanigan to begin the ninth inning. Hanigan was replaced by Devin Mesoraco as a pinch-runner. Mesoraco moved to second on a sacrifice bunt, but Rodriguez got a popout to third base by Miguel Cairo for the second out of the inning.
Then came the loss of control, as Rodriguez lost Stubbs and Heisey to walks and allowed Votto to come to the plate. Votto ended the game with a career-best six RBIs.
"I took a couple of good swings, missed them and fouled them back," said Votto. "That last one, I tried to make a choice and shorten up. The ball ended up carrying out of the ballpark, which is not that typical when you're shortening up and trying to put the ball in play."
Kevin Goheen is a contributor to MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.