DENVER — Sam Gaviglio's experience in the minor leagues helped him get his first win in the majors.

Gaviglio pitched into the sixth inning to get his first career victory, and the Seattle Mariners used six relievers to beat the Colorado Rockies 6-5 on Monday.

He was making his third start and fourth appearance after beginning the year with Triple-A Tacoma in the Pacific Coast League. His time there helped him in the thin air at Colorado.

"It's like pitching in a PCL game," he said. "A lot of high-altitude parks."

Danny Valencia had three hits and Kyle Seager had a key double to help Gaviglio (1-1) get the milestone. The rookie allowed five runs on six hits and left after two singles to lead off the bottom of the sixth inning.

Both runners scored, but the bullpen blanked the hot-hitting Rockies from there.

"It's five innings in Coors Field," manager Scott Servais said. "We'll take it."

Gaviglio also got his first major league hit, a single to lead off the third, and scored the game's first run.

Charlie Blackmon and Trevor Story hit solo homers and Gerardo Parra got two hits and two RBIs for Colorado. Tyler Chatwood laboured through 4 2-3 innings in taking the loss.

"I don't think I executed where I wanted to do," he said. "I felt good overall, but I didn't execute the pitches when I needed to."

The Mariners gave Gaviglio a 6-2 lead with three runs in the third on just one hit — Gaviglio's single up the middle — and three more in the fifth on three walks, three singles and a two-run double by Seager off Chatwood (4-7).

The Rockies chipped away at the lead. Story homered in the fifth and an RBI double by Parra in the sixth made it 6-5. Seattle went to the bullpen to shut the door. Three relievers got through the eighth, and Edwin Diaz worked the ninth for his ninth save and just his second in three weeks.

"When you can work the game to have that anchor it is so, so valuable," Servais said. "We have the pieces to do that but you've got to have that guy at the back end and Eddie's confidence is growing. He looks the part again."

TRAINER'S ROOM

Mariners: Servais said LHP James Paxton (left forearm strain) will start as scheduled Wednesday after a successful rehab start. He has been out since May 3. ... RHP Felix Hernandez (right shoulder inflammation) will throw a bullpen session Tuesday. He has missed a month with the injury.

FOND MEMORIES

Rockies manager Bud Black was drafted by Seattle and made his major league debut for the Mariners in 1981. Black reminisced about his short time with the club, which ended with him being dealt to Kansas City during spring training in 1982.

"I pitched the seventh inning of an intrasquad game, which tells you where I was at in the pecking order, and (Rene Lachemann) was my catcher," Black said. "My manager was catching me. Two weeks later I got traded."

It turned out OK for Black. He had a 15-year career in the majors and was on the 1985 Royals team that won the World Series.

DEEP ROSTER

The Mariners have tested their depth early this season. Heading into Monday's game Seattle has made more than 80 player moves this season and employed 12 different starting pitchers.

"It's a great challenge. You are trying to create team environment and closeness, and it's hard," Servais said. "It's unheard of at this time of the season. Guys have stepped up and for the most part they have thrown strikes."

UP NEXT

Mariners: LHP Ariel Miranda (4-2, 4.22 ERA) has allowed only four earned runs over his last three starts. His ERA is 2.12 over that span.

Rockies: LHP Tyler Anderson (3-4, 5.40 ERA) is 2-1 with a 2.55 ERA and three quality starts in his last four outings.