Taylor Jordan cruises through five innings and then comes apart in the sixth. He leaves with a 4-2 lead but was charged with four runs over 51 / 3 innings. (Morry Gash/AP)

Into the sixth inning Sunday afternoon, the Washington Nationals exerted full control. Their rookie starting pitcher cruised, their offense hummed and their first road sweep of the season beckoned. They would fly back home for a now-or-never showdown, finally a chance to slow down the smoking-hot Atlanta Braves themselves.

In baseball in general and for these Nationals in particular, control is an illusion. One crucial hit bounded over their third baseman’s head. Another probably should have been ruled a foul ball. A third fluttered to the turf over scrambling, drawn-in infielders. Suddenly, the combined assault of the Milwaukee Brewers and misfortune created a ruinous, five-run inning and led ultimately to an 8-5 Nationals defeat at Miller Park.

Starter Taylor Jordan and reliever Fernando Abad combined to allow five runs in the sixth as the Nationals squandered a three-run lead. They let a victory slip away at a juncture when they cannot afford to let victories slip away. By the end of the night, the Nationals sat a season-high 121 / 2 games behind the first-place Braves, who beat the Phillies for their 10th straight win.

“We’re going to need to start playing better soon,” right fielder Jayson Werth said. “It’s surprising. It’s really tough to pinpoint. There’s probably a lot of reasons why we’re here. But I still have hope. I still haven’t given up. I never will. But, yeah, it’s surprising.”

With 51 games left in the wake of a 2-3 road trip, the Nationals recognize how little control they really have. They sit 61 / 2 games behind the Cincinnati Reds, making the second wild card a more vivid possibility. They also know they cannot become preoccupied with the standings before they start to play better.

“We’re totally worried about ourselves,” first baseman Adam LaRoche said. “I think individually, we’ve probably spent too much time worried about who we’re playing, what they’re doing, their strengths, instead of worrying about our strengths and what we do best. In the situation we’re in in the standings, it really doesn’t matter. We just need to win games.”

On Sunday, LaRoche gave the Nationals a 4-1 lead in the sixth when he blasted John Axford’s 95-mph fastball to the upper deck in right field. His second homer in as many days seemed to provide cosmetic insurance. The Nationals had held the Brewers to two runs all series, and Jordan had allowed two hits and a walk through five innings.

“Everything seemed to be working how I wanted it,” Jordan said. “Then the sixth inning came around, and something changed.”

Jordan, who underwent Tommy John surgery in 2011, has never before pitched as much as the 131 innings he has thrown between the minors and majors this year. He will make four more starts, he said, before he reaches a team-mandated innings cap. Even though he threw only 85 pitches, the workload may have caught up to him.

“I started running out of gas,” Jordan said. “The balls were elevated a little bit. I was trying too hard. I think I lost a little bit of life. The ball started to cut a little bit.”

In their third time through the order, as a fastball that had zipped at 95 in the first inning dropped into the low 90s, the Brewers struck. Logan Schafer singled, Jean Segura doubled and Jonathan Lucroy walked to load the bases. Carlos Gomez laced a sac fly to right field, and with the score 4-2 Manager Davey Johnson wanted a change.

“He battled,” catcher Kurt Suzuki said. “I just think he just ran out of gas.”

With left-handed hitters Caleb Gindl and Juan Francisco due up, Johnson asked Abad to rescue Jordan. Johnson chose Abad over Ian Krol, his usual go-to lefty, for two reasons. First, Abad was more rested. Second, Johnson thought the Brewers might pinch-hit for one of the left-handed hitters. In that case, right-handed batters had produced a .568 on-base plus slugging percentage against Abad compared to .670 against Krol.

Johnson guessed right — Milwaukee Manager Ron Roenicke sent Khris Davis to hit for Gindl. Davis chopped an RBI single over Ryan Zimmerman’s head, and the Brewers’ third run scooted home. Francisco hit for himself, and he bounced a ball down the first base line.

LaRoche gave chase before it kicked into the corner. Replays were inconclusive, but the ball appeared to bounce to the right of the first base bag.

“Close,” LaRoche said. “But foul.”

Rather than a foul ball, Francisco had a game-tying RBI double. With the score knotted and the infield playing in, Jeff Bianchi blooped a single to shallow center. Anthony Rendon and Ian Desmond desperately gave chase as two more runners crossed. The Brewers led, 6-4.

“He made some good pitches,” Johnson said. “They just nicked him to death.”

Even after Rendon homered to make it 6-5, the Brewers added on, scoring on a Lucroy groundout in the seventh and taking advantage of a rare error by Desmond to push across another run in the eighth. The Nationals could rightfully bemoan their bad luck. But they also went 2 for 11 with runners in scoring position, hit into three double plays and stranded five runners.

“We had plenty of opportunities to add on,” Johnson said. “We just didn’t do it. That’s been kind of the whole scenario all year — get runners in scoring position and don’t swing the bat, get the big hit. That was extremely tough. We got a three-run lead late in the ballgame. We should be able to hold it.”