PHOENIX -- Dodgers closer Kenley Jansen said he's significantly improved from his diagnosis of an irregular heartbeat and could return to action next Tuesday night when the club opens a three-game series at Washington.

"I've just been trying to stay in shape and stay sharp. I'm feeling great," Jansen said prior to Wednesday night's game against the D-backs at Chase Field. "Those days that I missed I don't feel like I've got to get back into it. I feel ready. I could go out and pitch today if they needed me. But I can't. I've got to get off the blood thinner first. That's how good I feel."

Jansen hasn't pitch since Aug. 27 when he felt his heart accelerate and experienced a loss of breath and dizziness. He was diagnosed with atrial fibrillation, a malady that affects more than 50 percent of the U.S. population. The condition contains a slight higher risk of blood clots in the chamber of the heart, which is the reason Jansen was placed on a blood thinner.

Two days after he comes off the thinner he'll be eligible to pitch. Club physicians are concerned that Jansen would be subjected to excessive bleeding if he receives a wound while pitching. That could be dangerous.

"They're concerned that if a ball came back at me it could hit me," he said.

Jansen is scheduled to stop taking the medication on Friday. Because the club is traveling on Monday he should be cleared to return the next day. He'll undergo a procedure during the offseason to try to shock his heart back into regular rhythm.

"It's not a big deal," he said. "I just have to get it done so I don't have to worry about it in the future."

Jansen is 5-3 with a 2.54 ERA and 25 saves in 56 appearances.

Kemp, Adrian swap spots in tweaked LA lineup

PHOENIX -- The Dodgers have scored 11 runs in losing five of their last six games, including consecutive shutouts, leading manager Don Mattingly to tweak the lineup a bit for Wednesday night's game against the D-backs at Chase Field.

Mattingly flip-flopped Matt Kemp and Adrian Gonzalez in the batting order, moving Kemp up to third and Gonzalez into the cleanup spot.

Mattingly admitted that the move was purely psychological and might not have much impact. But he's willing to try anything right now with the team struggling for a playoff spot and only 20 games left to play.

"I can't say I'm doing it for any crazy reason except it's something different," Mattingly said. "It's just a little switch as much as anything else. It's the same group of guys, but just a little bit of a different look. [It's psychological] as much as anything."

Kemp missed two games this past weekend at San Francisco after injuring his left shoulder last month crashing into the center-field fence at Coors Field. He took three days in a row off, had an MRI and a cortisone shot and returned to the lineup on Tuesday.

Mattingly admitted on Wednesday that Kemp will probably be playing at less than 100 percent for the rest of the season. He already missed 51 games earlier in the season because of a severe left hamstring strain and since returning from the hamstring injury on July 13, he's had just six homers and 28 RBIs.

In the 1-0 loss to Arizona on Tuesday, Kemp and Gonzalez combined to go 1-for-7 with Kemp's seventh-inning double one of only five Los Angeles hits in the game.

The Dodgers made the mega trade with Boston on Aug. 25 that netted them Gonzalez, Josh Beckett, Nick Punto and Carl Crawford, who is out until midway through next season after Tommy John surgery on his left elbow. The Dodgers are 6-10 since the big deal and have lacked collective cohesiveness, Mattingly said.

"You can't blame it on one guy," he said. "We have to put these guys together as a team. And it's important that we play that way. We just don't have 162 games to do it. We have 30 games."