ATLANTA -- Catcher Jesus Flores sustained a strained right hamstring in the Nationals' 7-2 victory over the Braves on Sunday night. The injury is not considered serious and he is listed as day to day.

Flores, who went 3-for-4 in the game, felt the injury in the sixth inning when he scored on a double by Steve Lombardozzi. Flores told manager Davey Johnson that he could complete the game, but he was taken out in the seventh after getting a base hit and running to second base on a sacrifice bunt by Gio Gonzalez. Flores was replaced by Carlos Maldonado.

"I don't think it's a big deal, but we want it to be safe and avoid any risk of any [serious] injury," Flores said.

Maldonado is expected to start against the Marlins on Monday and the team is hoping that Flores can get back on the field Tuesday.

Flores is the third catcher on the Nationals to be injured this month. Wilson Ramos is out for the year with a torn right ACL and Sandy Leon suffered a serious high ankle sprain and is expected to be out for a lengthy period.

Outside of Jhonatan Solano, the Nationals don't have catching depth in the Minor Leagues, so the Nationals need to acquire a catcher just in case Flores' hamstring doesn't get better.

Tracy to have MRI, roster move may come

ATLANTA -- Nationals infielder Chad Tracy said his right leg is still sore and he will get an MRI on Tuesday in Philadelphia. Tracy now believes that he has a groin injury, not broken-up scar tissue from a sports hernia he had last year. According to manager Davey Johnson, the injury isn't getting any better.

"My gut is, it's not the scar tissue, just because it's in a different spot. I think it's two separate injuries," Tracy said.

The injury occurred in Saturday's 8-4 victory over the Braves. With a runner on second and the game tied at 4, Tracy hit Kris Medlen's 1-0 pitch into the gap in left-center field for a double, scoring Ian Desmond. It was Tracy's Major League-leading ninth pinch-hit RBI, but he came up hobbling while running to second base.

Athletic trainer Lee Kuntz immediately came to Tracy's aid. A couple of minutes later, Tracy left the game.

Tracy is still not sure if he will go on the disabled list, but Johnson said the Nationals will make a decision on a roster move on Monday.

Meanwhile, outfielder Corey Brown was not in the lineup for Triple-A Syracuse for the second day in a row and is on his way to Miami to join the Nationals on Monday. It is still not known if he will be put on the 25-man roster.

Brown is having a nice comeback season, hitting .297 with 12 home runs and 30 RBIs for Syracuse. He has hit a home run in five straight games.

Johnson also has not ruled out Mark DeRosa being activated from the disabled list during the Marlins series. DeRosa, who hasn't played since late April because of a left oblique strain, took batting practice with the team on Sunday and had a throwing session without any problems.

"I'm hoping I'm activated pretty soon," DeRosa said. "I took BP today and I felt pretty good. I'll see how I recover tonight and get back in the cage [Monday] before the day game. We'll see where we are at."

Detwiler prefers starting, understands 'pen move

ATLANTA -- A day after being told he was being demoted to the bullpen, Nationals left-hander Ross Detwiler said he would prefer to be a starter, but understands why Chien-Ming Wang is being put in the rotation.

"We have a guy that is year in and year out winning games. I wasn't getting the job done at the time. I still have a chance to put on a big league uniform," Detwiler said. "The way I look at it, I'm going from the best starting rotation in the big leagues to the best bullpen."

Just a few weeks ago, it seemed like a no-brainer that Detwiler would remain in the rotation, but he has not pitched well in his last three starts and has seen his ERA climb from 2.10 to 3.88. It also didn't help that he threw 100 pitches in 4 1/3 innings against the Braves on Friday.

"I didn't think the last start was as bad as it looked. I was just missing here and there. I thought that was an easier fix than anything else," Detwiler said. "I'm really looking forward to getting back out there and throwing strikes and not falling behind every hitter."

Wang, who started the season on the disabled list because of a strained left hamstring, made his season debut on Friday and pitched well, allowing one run in three innings to earn the win. Wang was slated to start the season as the fifth starter before he was injured.

"If he didn't get hurt, I wouldn't even have the chance to start games anyway. He is just coming back and claiming his spot. That's all it is," Detwiler said.

Detwiler will not be available to work out of the bullpen until Tuesday or Wednesday. He will be treated as if he will be a starter and will probably be available to pitch every fifth day.

Pitching coach Steve McCatty said that there is nothing wrong with Detwiler's mechanics. He needs to attack the strike zone better.

"It getting back to the trust of hitting your spots and being aggressive and say, 'Here, I'm going to put it in play.' Sometimes, when you struggle the worst you can do is try to do more," McCatty said.

Don't sweat it: Nothing wrong with Strasburg

ATLANTA -- During his outing against the Braves on Saturday, Nationals right-hander Stephen Strasburg was seen shaking his arm before throwing a pitch.

There is nothing wrong with his arm. He was simply trying to get the sweat off his arm and hand.

"When you sweat, you want to get it off your hand and, yesterday, the weather was pretty warm," pitching coach Steve McCatty said.

Strasburg earned his fifth win, allowing four runs in five innings.