ATLANTA -- A strained left hamstring will keep right fielder Lucas Duda out of the lineup for a few days, manager Terry Collins said on Saturday. The Mets hope that a few days of rest will be all Duda needs to get healthy.

"It's not a big deal," Duda said. "In a couple of days, I should be going."

Duda is available to pinch-hit, but Collins wants to give him a chance to rest.

"I just said, 'Look, we've got to get your leg right,'" Collins said. "Because if your leg is affecting your hitting, if it's affecting your trunk rotation and everything else, than it's got to get fixed."

Duda, who is hitting .247 and is tied for the team lead in home runs, with 12, said the hamstring has been bothering him for a few weeks. He hoped the issue would be resolved during the All-Star break, but Collins said it "stiffened up."

Duda has slumped throughout July and is hitting .143 with just one extra-base hit in eight games this month. Collins said that Duda hasn't used the injury as an excuse for his recent struggles.

"He will say no," Collins said. "I'll support that, but I'll imagine it hasn't helped."

Batista or Harvey could be Mets' fifth starter

ATLANTA -- With right-hander Chris Young on track to start on regular rest on Wednesday against the Nationals, the Mets will not need a fifth starter until Saturday, against the Dodgers. Manager Terry Collins said the decision will come down to right-handers Miguel Batista and Matt Harvey.

Batista is the Mets' long man out of the bullpen but has made four starts this season. In those starts, he is 1-1 with a 4.00 ERA over 18 innings. Harvey, the Mets' No. 2 prospect, is pitching for Triple-A Buffalo. He is 7-4 with a 3.39 ERA and has struck out 102 batters in 98 1/3 innings

Harvey will start for Buffalo on Monday, and he will be closely watched by the Mets.

"Monday night, we might get the reports back [saying] he's the guy, he's ready," Collins said.

Collins also did not rule out the possibility of right-hander Zach Wheeler, the Mets' top prospect, being called up to the Major Leagues this season.

"I've heard wonderful, wonderful things about him," Collins said. "Getting better, getting better, getting better. He's not out of the mix."

Wheeler, who was acquired in the Carlos Beltran trade, is 8-4 with a 2.62 ERA at Double-A Binghamton this season, and he may be in line for a promotion to Triple-A soon.

Collins makes best of teachable moment for Edgin

ATLANTA -- As a former director of player development and Minor League field coordinator, Terry Collins has a strong background in teaching baseball to young players. Though that role has to take a backseat now that he is the Mets' manager, he still values the opportunities he does get to teach.

Even though the Mets are in the mix for a playoff spot at the outset of the second half, Collins said the learning can't stop.

"We can't stop the development of our young players," Collins said. "Just because they've been here for three months now, we just can't throw up our hands and say, 'I hope they got it.' That's not how it is. It's a constant process."

Collins took advantage of one teachable moment in Friday's 7-5 loss to the Braves. Left-hander Josh Edgin made his Major League debut, entering a bases-loaded, one-out situation in the fifth inning. Edgin got out of the inning unscathed and retired the first two batters he faced in the sixth inning.

Then, however, he ran into trouble. Chipper Jones hit a 3-2 hanging slider into the center-field seats, and Freddie Freeman followed with a double off the wall in right field. Collins took Edgin out of the game, then made sure to explain where the inning had gone wrong.

"The one thing we went over was, he's got to have a big, broad idea of the situation at hand," Collins said.

Collins told Edgin that after getting the right-handed-hitting Martin Prado to fly out to start the inning, he then needed to focus on retiring Jason Heyward and Freeman, the left-handers surrounding switch-hitter Jones.

"When you got Prado out, all of a sudden, it becomes Heyward, Freeman," Collins said. "You can't let the guy in the middle beat you. So when you've got 3-2 on him, you've got to say, 'He's got to hit my pitch.' You don't have to throw a strike there."

Worth noting

• Left fielder Jason Bay will make another rehab appearance on Saturday, this time with Triple-A Buffalo. Manager Terry Collins said that Tuesday remains a realistic target for Bay to return from the seven-day disabled list.

• Outfielder Mike Baxter will begin his rehab process on Sunday with a game for high Class A Port St. Lucie. Baxter is on the 15-day disabled list with a displaced right collarbone.