NEW YORK -- There was no music blaring in the Atlanta clubhouse. Braves players spoke in hushed tones and hoped for the best. Far from a typical atmosphere after a bounce-back win.
"We won, but it's a tough night," catcher Brian McCann said.
Hudson took a shutout into the eighth inning before Eric Young Jr. inadvertently stepped on the back of the pitcher's lower right leg while trying to beat out a grounder. The 38-year-old right-hander with 205 career wins was carted off the field in obvious pain and had X-rays at Citi Field.
He will have surgery in Atlanta once the swelling goes down, leaving the NL East leaders without a veteran winner who was on a roll.
It's unclear how long Hudson will be sidelined or whether he'll be able to pitch again this season. Regardless, the Braves know they'll be minus one of their top pitchers for an extended period. They've built an eight-game cushion in the division, but losing Hudson could damage their postseason chances.
"It's terrible," second baseman Dan Uggla said. "That's a big blow."
Hudson (8-7) was working on a four-hitter when Young hit a grounder that was knocked down by first baseman Freddie Freeman. Hudson took Freeman's toss at the bag just before Young arrived, and the speedy outfielder accidentally drove the pitcher's right ankle awkwardly into the ground.
"I flipped and spun," Freeman said. "I didn't see it and I don't want to see it."
Hudson immediately went down in obvious pain, and Young rushed over to check on him. Braves manager Fredi Gonzalez and a trainer also ran out to aid Hudson, who took off his cap and held his shaved head in his hands.
The crowd at Citi Field groaned when the replay was shown on the big video board. Gonzalez said he hadn't seen it -- and wasn't sure he wanted to.
"He was kind of in disbelief," Uggla said about Hudson, who has overcome Tommy John surgery and back surgery within the past five years. "You could see the thoughts running through his head: This can't be happening. This is unbelievable."
EMS workers finally strapped Hudson to a backboard and drove him off the field on a cart as fans applauded.
Young remained nearby throughout the entire delay, which lasted almost 10 minutes, and shook Hudson's hand before he was carted away. Hudson nodded back at him.
"I knew I didn't get any of the base. I got all of his foot," a somber Young said. "I pretty much knew it was broke right when I did it. That's why I ran back to him and tried to console him as much as I could and to apologize."
Hudson won his fourth straight start, striking out nine in 7 2/3 innings -- his most since fanning 10 Mets on June 17, 2011. Luis Avilan replaced him and gave up a two-run double to Daniel Murphy, who made two errors at second base.
Hefner (4-8) compiled a 1.76 ERA in his final eight starts before the All-Star break, the best mark in the majors during that span. But he was tagged for a career-worst eight runs and 10 hits in two-plus innings last Friday against Philadelphia, a personal nemesis throughout his two-year career.
The right-hander wasn't much better against Atlanta, allowing a career-high three homers in 4 1/3 innings. All of them were no-doubters, too.
"Obviously coming out of the break, he's not the same guy he was going in," Mets manager Terry Collins said.
Gattis hit a solo shot into the second deck in left field in the second inning, his first home run since June 10 in San Diego. Despite spending 24 games on the disabled list with a strained muscle on his right side, he leads major league rookies -- by a wide margin -- with 15 homers and 39 RBIs.
McCann reached on an error to start the fifth when Murphy, playing deep on the outfield grass, bobbled an attempted backhand. Gattis singled and Uggla drove the next pitch to left for his 20th home run.
Chris Johnson singled and, one out later, Simmons teed off on a 2-2 breaking ball to make it 6-0.
Simmons also hit a leadoff homer Tuesday night for Atlanta's only run.
"Obviously, it's frustrating. The team is playing well, we're playing good defense and we're scoring runs and I'm not holding up my end of the deal," Hefner said. "To have my performance tonight is unacceptable."
Braves RHP Brandon Beachy, recovering from Tommy John surgery in June 2012, was set to make another rehab start Wednesday night for Triple-A Gwinnett. With Hudson hurt and LHP Paul Maholm (bruised left wrist) about to go on the 15-day disabled list Thursday, Beachy could be back in the rotation soon. ... Rookie left-hander Alex Wood will be called up to start the series finale Thursday in Maholm's place. The 22-year-old Wood (0-2, 2.45 ERA) has made 16 major league appearances but only one start, when he lasted three innings in a June 18 loss to the Mets. He has since been stretched out in the minors, and Gonzalez said Wood could be pushed to about 90 pitches Thursday. ... Gonzalez said Maholm will make a minor league rehab start before returning from the DL. ... RHP Zack Wheeler (3-1, 3.58) pitches for New York on Thursday. The prized rookie threw six shutout innings at Atlanta to win his big league debut June 18.