ATLANTA — Sergio Romo insisted he didn't blow his cool.
He couldn't deny he blew the save.
The Giants' closer forced in the tying run with a bases-loaded walk to Justin Upton and then gave up the game-winning single to Freddie Freeman, yielding two runs in the ninth inning of Saturday's 6-5 loss to the Atlanta Braves.
"That's baseball," Romo said. "You cannot control certain things. I went out there and I tried my best. It didn't go so well. It's never a good feeling when you let your team down."
B.J. Upton hit two homers off Giants starter Chad Gaudin, but San Francisco led 5-4 entering the ninth.
Romo (3-3) walked pinch-hitter Evan Gattis, who was replaced by pinch-runner Reed Johnson, with one out. Andrelton Simmons followed with a grounder that skipped past third baseman Joaquin Arias for an error, putting runners on first and second.
Jason Heyward followed with a liner that fell in front of left fielder Andres Torres, loading the bases.
Justin Upton took a close 3-2 pitch for a ball to force in the tying run. The pitch, which had Upton backing away, was close to the inside part of the plate. Romo took a few steps toward the plate to express his disagreement.
"It was a close pitch but I obviously think it's a ball," Upton said. "Pitchers want that pitch. It went my way."
Added Upton: "I've seen him a few times so I know what to look for."
Asked about the 3-2 pitch, Romo said "It really doesn't matter what I think. The outcome of the game is already settled."
Romo said he didn't let the walk affect his concentration against Freeman.
"I was fine," he said. "I had to focus. We were still in the game. Although they tied the game we still had an opportunity to keep playing. You got to dig down deep right there and stay focused."
Romo threw Freeman two sliders — one ball and one strike — before trying to sneak a fastball past the big first baseman. The left-handed hitting Freeman turned on the pitch, lining the game-winning single to right field.
"I just put my foot down and swung when I saw the ball," Freeman said. "I don't look for anything. I just put my foot down and swing and hope for the best."
Romo took his third blown save in 19 opportunities.
Braves closer Craig Kimbrel (2-1) struck out Hunter Pence to end the ninth with runners on first and second. Pence drove in two runs.
Pinch-hitter Gregor Blanco led off the ninth with a single off Kimbrel, but he was thrown out trying to steal second base. Replays indicated Blanco may have beat the tag. The call proved important because Blanco would have scored from second when Tony Abreu doubled for his third hit.
Gaudin gave up four runs on eight hits in five-plus innings.
Pence had a run-scoring single in the Giants' three-run third inning and a sacrifice fly in a two-run fifth. Braves starter Mike Minor gave up five runs, four earned, on seven hits and a walk in six innings.
San Francisco relievers Jean Machi, Javier Lopez and Jeremy Affeldt combined for three scoreless innings before Romo gave up two runs, one earned, on two hits and two walks.
B.J. Upton's long second-inning homer landed about halfway up the lower section of the left-field seats.
Upton's two-run homer to center field in the sixth drove in Brian McCann, who doubled. The homer cut San Francisco's lead to 5-4 and knocked Gaudin out of the game.
Simmons committed two errors after beginning the day with only four miscues for the season. Simmons' fielding error on Abreu's grounder led to an unearned run in the fifth. Buster Posey followed with a run-scoring double, which drove in Torres. Abreu scored on Pence's fly ball to right field.
Simmons made a wild throw after fielding an infield single by Juan Perez to open the sixth, but Minor pitched out of the jam.
The Giants took the lead in the third inning with three runs on four hits, including back-to-back RBI doubles by Torres and Abreu. Pence added a run-scoring single.
NOTES: The last time Gaudin allowed more than one homer in a game was Sept. 25, 2010, for the Yankees against Boston. ... Pence has a seven-game hitting streak and has RBIs in four straight games. ... Braves RHP Brandon Beachy, recovering from 2012 elbow ligament-replacement surgery, had been on target to make his 2013 debut on Tuesday before having tenderness in the elbow. Beachy had a MRI on Saturday and said the test showed he has only inflammation and no structural damage. ... The series ends Sunday night when Braves RHP Julio Teheran faces Giants RHP Tim Lincecum.