PORT ST. LUCIE, Fla. -- For the past month and a half, Noah Syndergaard has been feeling ill to various degrees. After the right-hander gave up three runs over 3 1/3 innings in the Mets' 6-4 win over the Marlins on Monday, New York revealed that he has been battling bronchitis.

"He's like many people, including myself, that when it gets in their lungs and they get bronchitis, it can affect you for a while," manager Terry Collins said. "He's fighting that. He's been on medication. He is getting better, but he just ran out of gas."

"I'm trying to get over it, but it is what it is," Syndergaard said. "I just want to be ready for Opening Day."

For the most part, Syndergaard has shown few effects of his condition, regularly hitting 100 mph during his first two scoreless spring outings. Monday, with his velocity sitting at 96-97 mph, Syndergaard did not allow a run until the fourth inning, when Marcell Ozuna hit an RBI double and Justin Bour followed with a two-run homer. Afterward, Syndergaard complained of fatigue, saying his "delivery was all over the place."

When asked if that was a direct effect of his illness, Syndergaard said, "Could be. Could be that it's just Spring Training, getting the endurance and stamina up."

Though Syndergaard was ill enough this past Thursday for manager Terry Collins to send him home from camp early, the right-hander has yet to miss a start. He is scheduled to pitch the Mets' Opening Day game on April 3 against the Braves.

Anthony DiComo has covered the Mets for MLB.com since 2008. Follow him on Twitter @AnthonyDiComo and Facebook, and listen to his podcast.