Before the game, Dodgers manager Don Mattingly admitted he did not know if outfielder Andre Ethier was going to be ready for Saturday’s contest.

Ethier was feeling so under the weather that he needed IV treatment, but he said there was no way he was sitting out if he could help it.

“I was ready to go,” Ethier said. “The medical staff did a good job getting me out there and ready to go.”

Turns out Ethier provided a shot in the arm for the Dodgers.

Ethier hit a three-run homer in the fourth inning to ignite a comeback from an early four-run deficit and the Dodgers grabbed an 8-6 victory Saturday night over the Arizona Diamondbacks, L.A.’s sixth win in seven meetings against its NL West rival.

Ethier’s line-drive homer off Arizona rookie Mike Bolsinger over the right-field wall — his second of the year — awakened an announced crowd of 48,541 and helped a scuffling offense record the team’s largest comeback victory of the season.

“I think it changed the feel of the game,” Ethier said. “We had an early four-run deficit and we were back on our heels and not doing what we are capable of doing, but then we made adjustments and maximized our opportunities.”

The Dodgers also took sole possession of first place with the win and the San Francisco Giants’ 3-1 loss to the San Diego Padres.

Ethier became just the sixth Dodger to record 600 RBIs in his career, joining Steve Garvey (992), Eric Karros (976), Willie Davis (849), Ron Cey (842) and Bill Russell (627).

“I think it’s a by-product of being here so long, that you start to tally up a lot of organization stats,” Ethier said. “It’s more of an honor to be here that long and be able to produce.”

The Dodgers chased Bolsinger — who retired the first eight Dodgers he faced — in the fifth inning by loading the bases.

Adrian Gonzalez greeted reliever left-handed reliever Oliver Perez with a two-run single, and Matt Kemp followed with a two-run double down the left-field line for an 8-6 lead.

“Big hits and runners on base — we didn’t do too much of that last night,” Kemp said.

Gonzalez had already extended his hitting streak to 14 games with a single in the fourth inning that fell just in front of a diving Gerardo Parra in center field. He is hitting .345 (20 for 58) with five doubles, five homers and 16 RBIs in that span..

Gonzalez’s go-ahead two-run single put the Dodgers ahead to stay.

“I was looking for something in the middle of the plate and was trying to give us the lead,” Gonzalez said. “The only thing I didn’t want there was a strikeout. It was a fastball over the plate, and I was able to get it in play.”

While Ethier and Co. provided a shot in the arm, Dodgers starter Dan Haren gave the bullpen a chance to rest and recuperate with seven quality innings to improve to 3-0 on the season.

“I was just trying to get through the eighth to get our guys a little more rest,” Haren said.