DENVER -- The Giants were in need of a jolt to wake up their sluggish offense and keep their latest downturn from spiraling even further. They found one in Evan Longoria. 

Longoria crushed his first grand slam in nine years and added a few defensive gems at third base to carry the Giants to a 9-8 win over the Rockies in 11 innings on Sunday afternoon, snapping their four-game skid and helping them avoid a sweep at Coors Field.

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“On a day like today where he just sort of took the game over and looked like kind of the best all-around player on the field, you recognize how much he has left in the tank,” manager Gabe Kapler said. “It’s a lot. He’s still an excellent athlete, capable of changing the game with his glove and his bat and his presence. We saw that on display today.”

Longoria’s seventh-inning grand slam off left-hander Kyle Freeland put the Giants ahead, 6-2. But the Rockies pulled within three on Elehuris Montero’s solo shot off Jakob Junis, and they scored three more runs off relievers Tyler Rogers and Jarlín García in the eighth to tie the game and force extras.

The Giants and Rockies traded a pair of runs in the 10th before San Francisco pulled ahead for good in the 11th, when automatic runner Mike Yastrzemski advanced to third on LaMonte Wade Jr.’s sacrifice bunt and scored on Wilmer Flores’ sac fly to snap an 8-8 tie.

Longoria capped his vintage performance by teaming up with Wade to make a superb defensive play in the bottom of the 11th. Automatic runner Sam Hilliard attempted to advance to third on Wynton Bernard’s fly ball to right field, but Wade made a perfect throw to Longoria, who managed to slap a tag on Hilliard’s cleats for the final out of the game. Hilliard was initially ruled safe, but the call was overturned following a replay review.

“I knew I touched him, and I purposely put myself out in front of the bag to be able to get his foot hopefully before he got to the bag,” Longoria said. “So really the credit goes to LaMonte. He put the throw right on the money, gave me a chance to put the tag on. But [Hilliard’s] a pretty tall guy. I didn’t know if he was actually touching the bag when I touched him. But it kind of went according to plan.”

Added Wade: “I just got rid of it quick, tried to get it over to Longo and let him do his thing.”

Longoria, a three-time Gold Glove Award winner, delivered another defensive highlight in the ninth, barehanding a chopper off the bat of Garrett Hampson before firing to first base for the out.

“I’ve made a few of them, but none like that,” Longoria said. “A guy that can run like that, it’s really a do-or-die play.”

It has been a challenging season for the 36-year-old Longoria, who has endured three stints on the injured list due to finger, oblique and hamstring injuries. But he has shown that he can still be a difference-maker when healthy and spur a Giants offense that entered Sunday averaging only 3.5 runs per game since the All-Star break, 26th in the Majors.

Longoria appeared to break the game open in the seventh when he snapped a 2-2 tie with the fourth grand slam of his career and his first since May 6, 2013. Yastrzemski led off the inning with a single to center field that ended an 0-for-29 drought, the longest hitless streak of his career. A double by Austin Slater and a walk by J.D. Davis loaded the bases with one out, prompting Rockies manager Bud Black to emerge for a mound visit with Freeland, who was at 99 pitches.

Black decided to leave Freeland in to face Longoria, but the move backfired. Longoria sent the first pitch he saw -- a fastball down and in -- over the left-center-field wall, causing Freeland to double over in disbelief and the Giants’ dugout to erupt in cheers.

“It wasn’t a bad pitch,” said Longoria, who is now 10-for-30 (.300) with five extra-base hits since returning from the IL on Aug. 8. “It was a ball off the plate and right at the bottom of the zone. But it was right where I was looking for it.”

The Giants, who are six games behind the Phillies for the third National League Wild Card spot, remain on the fringes of the playoff race. But Longoria said their ability to overcome a couple of blown leads late in the game showed that they still have some fight left.

“It’s good to see because it’s pretty easy to just roll over and quit in games like that when they come back,” Longoria said. “We’re up, they come back, they tie the game. And here we go again. We just got walked off last night. We’ve been struggling. There’s a lot of factors where you could just give up. But there are still signs of life in here. Guys are giving it everything they’ve got, so we’ve just got to continue to have that attitude every single day.”