The right fielder's first home run in the game came in the first off Giants starter Tim Lincecum on a 3-1 pitch. Jones was able to hit a ball he said was left over the plate, although he initially thought it was only going to be a double off the wall.
"I didn't really hear that much about him," Lincecum said. "He obviously has a [heck] of a swing."
As for the game-ender, Jones had no doubts about that one leaving the park as he became the 20th player to hit a home run into the Allegheny River.
Jones was greeted by his teammates at home plate. He has now hit a home run in four consecutive games and has hit seven long balls in his first 12 games with Pittsburgh.
"I'm just trying to take the same approach to every game," Jones said. "Just stay relaxed mentally and just take each at-bat, get a good pitch to hit and not try to do too much -- keep it simple. That's working for me so far."
The shot to center in the 14th came after the Pirates didn't register a hit from the eighth through the 13th. Only three batters reached during that span, all on walks.
But the Bucs' bullpen was just as stingy, as the Giants had only four hits after the seventh. Jeff Karstens was especially effective, throwing two scoreless frames on 15 pitches. He hasn't given up a run in his past four appearances. Evan Meek pitched a scoreless 14th for his first career victory.
The matching of the zeroes came after the Pirates' Paul Maholm and Lincecum did the same earlier. Each gave up just one run, with Maholm lasting eight innings and Lincecum seven.
Lefty Maholm limited the Giants to four hits -- all singles. He didn't allow a baserunner after Juan Uribe's two-out single in the second until the seventh, as he retired 13 consecutive batters.
The seventh inning was the first time Maholm was in a jam. Randy Winn and Pablo Sandoval singled before back-to-back outs left Maholm on the cusp of escaping danger. But Winn, who had earlier stole third, raced home as Pirates catcher Ryan Doumit tried to get Sandoval, who was heading to second on Maholm's wild pitch. The pitch bounced in front of Doumit, whose throw to second got away from Freddy Sanchez to allow the unearned run to score on Sanchez's error.
"When they scored the run late in the game, we were just kind of like, 'All right, it's battle of the bullpens,'" Karstens said. "We were going through their stats, and we know they have a good bullpen."
It marked the second time this season a lone run against Maholm was unearned. The previous time was June 11 against the Braves.
Regardless, it was Maholm's longest outing of the season. He threw 104 pitches, the first time he had thrown more than 85 since June 16. It was also the first time Maholm didn't give up a walk in a start since Aug. 13, 2008.
"I felt good," Maholm said. "I think my breaking ball was there for strikes a lot. My changeup was a lot better than it has been. It was mainly just getting ahead and spreading it in the zone and making them hit my pitch."
Despite giving up the lead, Pittsburgh almost regained it in the next half-inning, but Brandon Moss was thrown out at the plate by Winn, despite ramming into catcher Bengie Molina.
Earlier, when Maholm struck out Lincecum in the third, he already topped his strikeout total for his past two starts, which was three. He later stretched his total to seven, which tied for second-most strikeouts he's had in a start this season.
But the bats behind Maholm struggled against Lincecum, who has given up just 13 runs in his past 11 starts.
Jones' deep fly to center in the first meant last year's Cy Young winner surrendered just his fifth home run this season and first against a National League foe since June 7.
Lincecum struck out 10 in the game, the fifth time he's reached double digits this season.
Only four players registered a hit for Pittsburgh, with Sanchez nabbing two of the team's five hits against Lincecum. The second baseman hit his 28th double of the season in the fourth.
At game's end, the Pirates endured a rain delay, 12 straight scoreless offensive innings, two sing-a-longs of "Take Me Out to the Ball Game," 14 innings and 13 total pitchers -- and came out with a win.
"We didn't want to take that long, but we'll take it," manager John Russell said.