SAN FRANCISCO -- The San Francisco Giants added to their major-league lead in walk-off wins Sunday.

It came from an unusual source.

Conor Gillaspie followed a double by Ramiro Pena with a double of his own into the right-field corner, providing the Giants an 8-7 win over the Philadelphia Phillies.

The Giants' 19th one-run win of the season was their seventh in walk-off fashion. Gillaspie became the fifth to play the hero's role, with Brandon Crawford and Buster Posey the only two who have done it twice.

"It's that way every game here. It seems like somebody different steps up," said Gillaspie, who had a part in the Giants' May 7 walk-off win when he scored on Matt Duffy's game-winner. "This organization, the guys they bring in, they all feel they can contribute. I'm very grateful to have an opportunity to play in this organization."

Angel Pagan had four hits, scored three runs and drove in a pair for the Giants, who provided manager Bruce Bochy with win No. 800 in his San Francisco career.

"That just means I've been around a long time," Bochy downplayed. "It would have been a tough one to let get away."

The Giants blew 5-1, 6-5 and 7-6 leads earlier in the game.

The consecutive hits by Pena and Gillaspie came after Phillies right-hander Severino Gonzalez (0-10 had gotten Jarrett Parker to pop out leading off the ninth.

Cory Gearrin (3-0), the fourth Giants pitcher, got the win after escaping a two-on, two-out jam in the top of the ninth.

The win for the Giants was their 13th in their last 15 games overall, 13th in 16 at home and 14th in 18 against the Phillies.

"We battled all day. I guess you could probably say the same thing for them," Gillaspie said of the Phillies, who played the National League West-leading Giants to three one-run games in the series, winning the middle one. "It's a great thing to win a game like that."

The Phillies came from behind a third time in the eighth inning when a double by Cody Asche and single by Carlos Ruiz produced a run that forged a 7-7 tie.

"San Francisco is a good team," Phillies manager Pete Mackanin proudly stated, "and we were a little bit of a thorn in their side in this three-game series."

The Giants had gone up by one an inning earlier on a double off the bricks in right-center field by Pagan, who was thrown out at third attempting to stretch the hits into a triple.

Neither starting pitcher recorded a decision on a day when both struggled.

The Phillies' Aaron Nola was the first to get pulled, having allowed five runs on 10 hits in 3 1/3 innings. It was the right-hander's fourth straight start in which he failed to get through the fourth inning, a stretch in which he's been tagged for 25 runs.

Nola struck out five and did not walk a batter, but he did hit three, including consecutive batters in the Giants' four-run third inning. He became just the fourth pitcher in the majors this season to hit three batters in the same game.

The third hit batsman, Gillaspie, came with the bases loaded and capped the Giants' four-run third. Pagan and Posey had RBI doubles and Parker a run-scoring single earlier in the inning.

The Giants' Johnny Cueto couldn't hold a 5-1 lead, unraveling after plunking the Phillies' Maikel Franco with two outs and nobody aboard in the fourth inning.

The fastball to Franco's ribs, which came after all three of Nola's hit batsmen, drew a warning to both teams and, according to Cueto, got him on home plate umpire Doug Eddings' bad side.

"After I hit Franco, then the strike zone changed dramatically," Cueto insisted. "There was no intention (to hit Franco). I don't understand why he gave me a warning when their pitcher hit three of our guys."

Franco said he expected Cueto to retaliate for Nola's wildness.

"Everybody got upset," he claimed. "This is part of the game. I knew something was going to happen. I knew he was going to hit somebody."

Cueto lost the lead by allowing two runs in the fourth and two more in the fifth. He later surrendered a solo home run to Odubel Herrera in the seventh after the Giants had regained a 6-5 lead.

Long having failed to record a 10th consecutive start allowing two or fewer runs, Cueto was pulled two batters into the seventh, having allowed six runs on eight hits in his six-plus innings. He walked two and struck out two.

Ruiz and Freddy Galvis had RBI singles in the Phillies' two-run fourth against Cueto. Asche tied the game at 5-5 in the fifth with a two-out, two-run single.

Brandon Belt, Posey, Crawford, Pena and Gillaspie had two hits apiece for the Giants, who totaled 16 in the game. Crawford and Gillaspie joined Pagan with two RBIs.

Peter Bourjos had three hits for the Phillies, who haven't won a series at AT&T Park since May 6-8, 2013.

Herrera, Asche and Ruiz had two hits each for Philadelphia, which totaled 12. Herrera's homer was his eighth of the season.

NOTES: Giants 3B Conor Gillaspie's walk-off hit was the second of his career. His previous one came May 25, 2013 against Miami. ... Giants LF Angel Pagan went 8-for-13 with four RBIs in the three-game series. ... Bruce Bochy (800) ranks fourth on the all-time wins list for Giants managers behind John McGraw (2,583), Dusty Baker (840) and Bill Terry (823). ... San Francisco RHP Matt Cain (strained right hamstring) threw a bullpen session before Sunday's game and will throw live batting practice on Tuesday. He could make an injury-rehab start in the minor leagues later this week. ... The Phillies announced after the game that LHP Elvis Araujo was being sent to Triple-A Lehigh Valley to create a roster spot for RHP Vincent Velasquez (straight right bicep), who is scheduled to be reinstated from the 15-day disabled list in time to pitch Monday's series opener at Arizona.