(Patrick McDermott/Getty Images)

Edwin Jackson produced one of the worst outings of his career last week, a complete clunker in which in 56 pitches he produced only four outs but allowed the St. Louis Cardinals to smack six hits and score nine runs, eight of them earned.

On Wednesday  the veteran starter, as he has already shown this season, displayed his ability to pull himself together after bad starts. He tossed 6 2/3 strong innings, allowing only one run on six hits, striking out six and issuing only one walk.

He joined the rest of the Nationals starters, becoming the fifth to notch his 10th win of the season. (“It’s a good feeling to be the only one not left out of double digits [wins],” he said.) But more importantly for the Nationals, the right-hander found a groove that he hopes to continue into the playoffs.

“It definitely helps,” he said. “You keep the momentum in your favor. At the end of the day, positive or not positive, you have to be mentally ready to withstand what we’re about to see. It’s hostile environments wherever we go on the road. It’s definitely an adrenaline rush, and it’s definitely different from the regular season.”

Jackson is one of three pitchers on the current roster with playoff experience, but the lone one in the starting rotation to have pitched in the postseason. The 29-year-old won a World Series title with the St. Louis Cardinals last season and pitched in the World Series with in 2008 with Tampa Bay. While it’s unclear if he will be one of the Nationals’ four starters in the NLDS against Atlanta or St. Louis, he has the experience to handle the pressures of a postseason start if called upon.

Depending on how far the Nationals advance in the postseason and if Jackson is part of the rotation, Wednesday may have been his last start in a Nationals uniform. Jackson signed a one-year, $11-million deal, and despite some stretches of inconsistency, has been a valuable innings-eater. Though he finished with a 10-11 record, he logged 17 quality starts in 31 tries. He threw 189 2/3 innings, third-most on the team, 168 strikeouts and a 4.03 ERA. And, he has been a contributor behind the scenes.

“It kind of goes unseen, but Edwin has been the leader of our rotation all year long,” Ian Desmond said. “I don’t think he really minds the statistical stuff as far as ERA, wins, losses, that kind of thing. I think he wanted to bounce back from his last start, make sure his stuff is where he wanted it to be, and he did that. He came in and got a good day’s work against a good team.”

Added Manager Davey Johnson: “Getting to 10 wins, we all wanted him to get there. He has certainly pitched better to have 15 wins as good as he’s pitched.”

“Guys have the talent that they have and the physically abilities that they have, it’s amazing,” Jackson said. “For them to be so young, for them to be able to do what they do. For me to be able to come out and help them, regardless whether it’s actions or talking to them, whether it’s simple things, every little bit of information helps. These guys are going to be together for a long time. Every time they touch the field, every one has a chance to do something special.”

Before his clunker last week, he tossed a strong eight innings on Sept. 21 against Milwaukee. But preceding that, his previous three starts didn’t get past the six innings. Now, it’s up to Jackson, if asked to start in the playoffs or pitch out of the bullpen, to stay in the same groove he found on the mound Wednesday, evening out his recent up-and-down performances.

“You just have to be like that,” he said. “That’s one of those things that you teach without teaching. After you have a start that you don’t like, you just have to shake it off and have a short-term memory and come the next four days, or the next five days, ready to throw again. The last game is gone once you leave the field.”