PORT ST. LUCIE, Fla. -- When Braves manager Fredi Gonzalez delayed announcing his Opening Day starter in case an injury altered his plan, he was not necessarily preparing himself to deal with an ailment as potentially serious as the one Kris Medlen incurred while pitching against the Mets on Sunday afternoon.

Medlen exited the game in the fourth inning with what the Braves are calling a right forearm strain. The veteran right-hander will undergo an MRI exam and be further evaluated by the team's orthopedist, Dr. Marvin Royster, in the Orlando area on Monday.

While there is a chance Medlen will learn he needs to undergo Tommy John surgery for the second time in less than four years, the Braves are hoping for the best and hanging on to the optimism that they gathered after Mets physician Dr. Struan Coleman examined the pitcher Sunday afternoon.

"I feel a lot better talking to our medical people that we might be OK," Gonzalez said.

Gonzalez had no choice but to fear for the worst when Medlen immediately walked toward the dugout after throwing his second pitch to Mets first baseman Matt Clark with two outs in the fourth inning. Medlen had grabbed his elbow and walked toward second base to gather himself after he threw his first pitch to Clark.

"[Medlen] yanked a changeup. I've never seen that," Braves catcher Evan Gattis said, referring to the second pitch thrown to Clark. "Then, it was immediately right after he threw it. Right now, I'm just hoping for the best. We'll find out more tomorrow."

The always accommodating Medlen provided a sense of what he is feeling when he chose not to talk to reporters before exiting the stadium to make the 90-minute drive back to the Braves' Spring Training facility.

"He wasn't in good spirits [initially]," Gonzalez said. "But after he got settled down a little bit and the trainers looked at him a little bit and the Mets doctors looked at him, I think he was in better spirits."

Unfortunately, Medlen's reaction following Sunday's final pitch was similar to the one he had when he exited a start against the Mets on Aug. 4, 2010. He underwent Tommy John surgery two weeks later and then endured a long rehab process that sidelined him until the final week of the 2011 regular season.

Since returning from that procedure, Medlen has established himself as one of the game's most underappreciated pitchers. He has produced a 2.47 ERA in the 43 starts he has made since becoming a mainstay in Atlanta's starting rotation on July 31, 2012. Clayton Kershaw (1.80) is the only other pitcher who has produced a better ERA while making at least 40 starts during that span.

"You feel it's OK," Gonzalez said. "We're going to wait and see. Any time a pitcher walks off the mound and meets you in the foul line, you worry about that kind of stuff. But after all of that kind of settled down, we're optimistic that it's nothing major."

With Tim Hudson now with the Giants, Medlen stood as the obvious choice to serve as Atlanta's Opening Day starter. The Braves might now begin the regular season with their top two projected starters -- Medlen and Mike Minor -- both on the disabled list. Minor reported to Spring Training behind schedule because of the month-long stretch of inactivity he experienced after undergoing a urinary tract procedure on Dec. 31. He began throwing off a mound again last week and is still aiming to join Atlanta's rotation by the end of the regular season's second week.

If Minor and Medlen are both sidelined at the beginning of the season, Atlanta could open the year with a starting rotation that consists of Brandon Beachy, Julio Teheran, Alex Wood and Freddy Garcia. Courtesy of two early scheduled off-days, the Braves could use a four-man rotation until April 12. If Minor continues to progress like he has over the past couple of weeks, he would likely be ready to join the rotation before that date.

Gavin Floyd, who signed a one-year, $4 million contract with the Braves in December, is not expected to return from Tommy John surgery until the early portion of May. If he remains on schedule and extends the promise he has created during the early portion of camp, Floyd could provide the valuable depth the Braves envisioned when they took a gamble on him.

"You never feel like you have enough [pitchers] because stuff like this happens all of the time," Gonzalez said.