DENVER — Austin Gomber pitched effectively for six innings after spending a month on the injured list, and Dom Nunez hit a bases-loaded double in a five-run first as the Colorado Rockies beat the Seattle Mariners 6-3 on Wednesday.

Gomber (7-5) allowed three runs on three hits, all of them solo homers. He was reinstated earlier in the day after being out since June 20 because of tightness in his left forearm.

“A little bit excited, but I felt I was able to stay within myself and give the team a chance to win, eat up some innings and keep the pitch count down,” said Gomber, who threw 71 pitches, 42 for strikes, in winning his fourth consecutive decision. “It was good to get a win on the last day here before we head out on a long road trip.”

Kyle Seager, Luis Torrens, and Mitch Haniger all homered for the Mariners.

Daniel Bard pitched a hitless ninth, fanning Torrens for the final out, for his 15th save in 20 opportunities.

The Mariners chose longtime reliever Keynan Middleton (0-1) as their opener. But the Rockies jumped on him in his first career start.

C.J. Cron drew a bases-loaded walk, Charlie Blackmon had an RBI single and Nunez hit a two-out, three-run double for a 5-0 lead.

“Coming to the plate that first inning, I was trying to get a good pitch up, something I could handle and drive,” Nunez said. “Sure enough, I got it, put a good swing on it and good things happened.”

Darren McCaughan, making his major league debut, relieved Middleton to start the second and pitched five hitless innings. He walked three, struck out none and allowed a run on Raimel Tapia’s sacrifice fly.

McCaughan said a steady, determined mindset helped him put together a solid big league debut.

“I think just the mentality of attacking hitters has been really good for me, just getting in that mindset that I do belong here,” McCaughan said. “I’ve just got to take it one pitch at a time getting ahead, staying ahead. I think I made some strides and I’m just going to work on making my (pitching) arsenal better.”

Seager hit his 18th homer in the second. Torrens began the fifth with his 11th home run and Haniger connected in the sixth for his 23rd.

Haniger extended his hitting streak to 11 games and has reached base in 20 straight games dating to June 25.

UP NEXT — The Mariners return home to open a four-game homestand today against the Oakland Athletics with right-hander Chris Flexen (9-3, 3.35 ERA) set to pitch the series opener for Seattle against Sean Manaea (6-6, 3.28 ERA).

Seattle Colorado

ab r h bi ab r h bi

Crawford ss 4 0 0 0 Tapia lf 3 1 1 1

Haniger rf 4 1 1 1 Rodgers 2b 4 0 1 0

France 2b 4 0 0 0 Blackmon rf 4 1 1 1

Seager 3b 4 1 1 1 Story ss 4 1 1 0

Torrens 1b 3 1 1 1 McMahn 3b 3 1 1 0

Murphy c 3 0 1 0 Cron 1b 2 1 0 1

Kelenic cf 3 0 0 0 Bard p 0 0 0 0

Moore lf 3 0 0 0 Hilliard cf 3 1 0 0

Middleton p 0 0 0 0 Nunez c 2 0 1 3

McCaughn p 2 0 0 0 Gomber p 1 0 0 0

Swanson p 0 0 0 0 Givens p 0 0 0 0

Bauers ph 1 0 1 0 Hampson ph 1 0 0 0

Ramirez p 0 0 0 0 Estevez p 0 0 0 0

Fuentes 1b 0 0 0 0

Totals 31 3 5 3 Totals 27 6 6 6

Seattle 010 011 000 — 3

Colorado 500 100 00x — 6

DP—Seattle 1, Colorado 1. LOB—Seattle 2, Colorado 4. 2B—Nunez (10). 3B—Rodgers (2). HR—Seager (18), Torrens (11), Haniger (23). SB—Tapia (16). SF—Tapia (3). S—Gomber (6).

IP H R ER BB SO

Seattle

Middleton L,0-1 1 5 5 5 1 1

McCaughan 5 0 1 1 3 0

Swanson 1 1 0 0 0 1

Ramirez 1 0 0 0 1 2

Colorado

Gomber W,7-5 6 3 3 3 1 3

Givens H,8 1 1 0 0 0 1

Estevez H,9 1 1 0 0 0 1

Bard S,15-20 1 0 0 0 0 1

Umpires—Home, Ben May; First, Bill Welke; Second, Pat Hoberg; Third, Chris Conroy.

T—2:35. A—25,053 (50,445).