Jon Gray looked nearly untouchable Wednesday afternoon to start his first Rockies game back from the injured list.

The right-hander kept the Giants scoreless over five innings, struck out eight and drove in Colorado’s first run. But he got knocked from the game in the sixth and the Rockies predictably folded in a 7-4 defeat, allowing four runs in the ninth.

“(Gray) had solid velocity throughout the game. He held his stuff. … The mix was there. Five scoreless innings. He held them down and had some punchouts. I thought he threw the ball great,” manager Bud Black said. “Take away the first three or four batters in the ninth and I thought we pitched outstanding.”

Closer Carlos Estevez blew the game in the ninth.

The Rockies led 4-3 when he loaded the bases with no outs. San Francisco’s Lamonte Wade Jr. put the Giants ahead with a soft two-run RBI single to right. Soon after pinch-hitter Evan Longoria put the game away with a two-run double for a major-league-leading 90th victory.

It marks the first time the typically hot-at-home Rockies have been swept at Coors Field this season. Colorado (63-77) — with four consecutive losses — now embark on an 11-day, 10-game road trip at the Phillies, Braves and Nationals.

Catcher Elias Diaz homered in the sixth to put the Rockies up 4-3, his 16th blast of the year, soon after Gray was pulled.

Black pulled Gray with no outs after consecutive singles were followed by a three-run home run from Giants’ shortstop Brandon Crawford, tying the game 3-3.

But Gray reflected positively on the start. He threw strikes on 61 of 87 pitches.

“I felt really strong today. I didn’t feel like I let up on any pitches,” Gray said. “I felt like it was good to go. I had good results.”

Gray’s bat struck first to end the scoreless stalemate with an RBI single off San Francisco starter Anthony DeSclafani in the fifth. Charlie Blackmon grounded into a fielder’s choice that scored Gray. Then Trevor Story ripped a double that brought home Raimel Tapia, making it 3-0.

Rockies’ infielder Colton Welker, a 2016 fourth-round draft pick, made his MLB debut in the eighth inning. He ripped a deep fly ball to right-center that was caught near the wall.

Roster moves. The Rockies recalled Welker and right-handed pitcher Antonio Santos from Triple-A Albuquerque on Wednesday. Colorado has optioned infielder Joshua Fuentes to Triple-A.

The Rockies placed starting pitcher Chi Chi Gonzalez on the injured list with an oblique strain. The right-hander struggled in his last outing on Tuesday with five earned runs allowed on eight hits over just 1-1/3 innings. The Rockies also put right-handed pitcher Robert Stephenson on the paternity list.

On Deck

Rockies RHP Antonio Senzatela (4-9, 4.16 ERA) at Phillies LHP Ranger Suarez (6-4, 1.38 ERA)
5:05 p.m., Thursday, Citizens Bank Park
TV: AT&T SportsNet
Radio: KOA 850 AM/94.1 FM

Senzatela is set to make his 24th start of the season during a brilliant recent stretch. He is 2-0 over his last four outings with a 2.00 ERA. The right-hander has given up only two home runs over his past eight starts. But Senzatela has been far less effective on the road this season at 1-6 with a 4.56 ERA. Senzatela is winless (0-2) lifetime against the Phillies.

Trending: Southpaw Lucas Gilbreath, a Legacy High School graduate (‘14), has not been scored upon in 11 consecutive relief appearances.

At issue: The Rockies have allowed a combined 33 hits to opposing pitchers this season, the most in Major League Baseball.

Pitching probables

Friday: Rockies RHP German Marquez (11-10, 4.08) at Phillies LHP Bailey Falter (2-0, 4.94), 5:05 p.m., ATTRM
Saturday: Rockies LHP Kyle Freeland (5-7, 4.69) at Phillies RHP Zack Wheeler (12-9, 3.93), 4:05 p.m., ATTRM
Sunday: Rockies RHP Ryan Feltner (0-1, 20.25) at Phillies RHP Aaron Nola (7-8 5.57), 11:05 p.m., ATTRM