The decision gave Atlanta its first victory in five games this season over the Giants, who mustered three hits in 6 2/3 innings against Braves left-hander Mike Minor. Meanwhile, the Braves matched their run total for their previous four games against San Francisco.
But they needed some help against Giants starter Ryan Vogelsong, and got it.
The Giants entered the fateful sixth trailing 1-0 behind Vogelsong, who had surrendered a mere three hits and had already matched his personal regular-season best of eight strikeouts. "I feel like I probably threw the ball better tonight in the first five innings than I did in the previous three [games]," said Vogelsong, who recorded a 0.89 ERA in his previous trio of outings.
With Jason Heyward on second base and one out, Freddie Freeman singled to right field. Hunter Pence quickly scooped up the ball and unleashed a powerful throw, which reached Posey on the fly and beat Heyward by at least 20 feet.
But that extra time to make the play didn't help Posey, who reached toward Heyward to tag him but missed. Heyward slid neither head- not feet-first. Instead, he sprawled toward home plate and in doing so succeeded in skirting Posey and reaching around the catcher to brush the plate with his left hand.
Posey stood virtually motionless after Heyward was called safe, his body language reflecting his disappointment.
"It's a shame I missed [the tag]," Posey said. "Because that would have been a big out. It kind of flip-flopped the momentum."
Giants manager Bruce Bochy challenged the ruling, but video review confirmed the call.
"We had a view that made it look like [Posey] barely touched [Heyward]," Bochy said, explaining what prompted him to issue a challenge. Said Posey, "I was just guessing I might have nicked his jersey."
Observers theorized that the newly instituted rules discouraging home-plate collisions, which restrict the behavior of baserunners as well as catchers, may have influenced Posey's somewhat tentative approach, as well as Heyward's odd slide.
Referring to Heyward's hybrid slide/tumble, Bochy said, "The slides are getting creative."
Heyward admitted that without the new regulations, "I think a lot of things would have been different. I don't think he would have walked toward me. It was just weird. I knew immediately I couldn't hit him. I was shocked he walked toward me. But he was doing what he felt he needed to do. The only thing I had going for me there was he didn't know how I was going to react. Everyone was cautious. But the good thing is no one got hurt."
Bochy tried to remain positive, remarking that the Giants should "learn from this." Posey said his lesson was "probably to be more aggressive with the tag. ... If I could go back, I probably would have jabbed out a little more, at his ribs."
As Posey indicated, the inning continued to unravel. Evan Gattis walked and was forced out at second base by Chris Johnson. Yet the third out eluded Vogelsong (1-2), who surrendered RBI singles to B.J. Upton and Andrelton Simmons. Vogelsong denied that the Posey/Heyward play distracted him, saying, "I just didn't make very good pitches after that."
That was Vogelsong's final inning. Atlanta added a seventh-inning run off David Huff, who made his first appearance since April 21 after overcoming a strained left quadriceps.
Meanwhile, Giants hitters were helpless against Minor (1-2), who retired 16 consecutive batters after Pence drilled a one-out double in the first inning. San Francisco, which absorbed its second shutout defeat, went 0-for-7 with runners in scoring position. That included Posey's strikeout with runners on second and third with two outs in the bottom of the sixth, when a big hit would have made the game competitive and salvaged his evening.
Posey praised Minor's effort: "He had a good two-seamer going, better than I remember it."
Moving runners into scoring position in each of the last four innings accomplished nothing for the Giants, with the possible exception of keeping Atlanta manager Fredi Gonzalez on edge.
"Those guys scare me over there," Gonzalez said. "... When you play the Giants or Bruce Bochy, you're in it for 27 outs."