A cellphone video fueled a dream that Rockies right-hander Ryan Castellani finally lived Saturday night.

Castellani, making his Major League debut as a sub for the injured Chi Chi González, retired his first 12 batters before command deserted him in the fifth inning. The rookie, who was under a tight pitch count because he didn’t have Minor League work, gave way to the bullpen, and Jeff Hoffman, Yency Almonte and Phillip Diehl completed the sixth one-hitter in Rockies history, a 5-0 victory over the Mariners at T-Mobile Park.

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In 2014, Castellani -- who struck out three and departed after hitting a batter and walking another -- was a senior in high school at Brophy College Preparatory School in Phoenix when he shot the footage that guides him. His mother, Regina Castellani (a 30-year Phillies front office employee before the family moved west), allowed him to skip morning class to watch perennial Cy Young winner Max Scherzer throw an offseason bullpen session.

It just so happened that Castellani’s pitching tutor, Chris Sinacori, was working with Scherzer and was teaching Castellani some of Scherzer’s methods. Although Castellani’s motion from the stretch has evolved, and he developed some personal nuances through work with Rockies pitching coaches, the Scherzer footage on his phone is still a guide.

“I check in with it once a month or so, when I’m scrolling through my phone,” Castellani said. “There's just a lot of cues there that have helped me, you know, grow into the pitcher that I am.”

Charlie Blackmon ran his hit streak to 12 games, doubling twice -- the second for three runs to blow open the game -- on a three-hit night that lifted his batting average to .446. The Rockies, now 11-3, matched the 2011 club for the best 14-game start in club history. And the Rockies have won their first five series, even though their most recognizable star, third baseman Nolan Arenado, is batting .185 after going 0-for-5 on Saturday.

But the story was the pitchers, who combined for their first shutout of the season. Castellani joined a rotation that can brag that no member has given up more than three earned runs in any contest.

“Not added pressure, just more motivation to keep this going,” Castellani said. “I was on the taxi squad that first road trip and I’ve been around here seeing them throw. Obviously, the team is hot. The Rockies are in first place, which is huge.

“I know there’s that necessity to keep the tides going.”

Castellani, 24, imitated the rock and the hands above the head at the start of Scherzer’s windup, but had to wait for a chance to emulate the success. The right-hander took the long route to the Majors, after being selected in the second round in 2014. He hit each Class A level, spent two years in Double-A and, last year, was limited to 10 starts at Triple-A Albuquerque because of loose particles in the elbow, which were removed during the summer.

But Castellani’s 2.16 ERA in the 2019 Arizona Fall League, paired with encouraging work in Spring Training and Summer Camp, earned him a chance.

Called up after González became stricken with right biceps tendinitis, Castellani mixed a four-seam fastball up in the zone with a two-seamer down, and used a curve, slider and changeup -- a full package -- to keep the Mariners off balance.

He started with a three-pitch strikeout of J.P. Crawford, a sequence that manager Bud Black recounted for Castellani while removing him from the game in the fifth after he hit Kyle Seager and walked Daniel Vogelbach.

“I told him I’d always remember the breaking ball to J.P. Crawford, the first strikeout of his Major League career,” Black said. “That was cool. But the thing that was impressive to me was, you know, just his mound presence. His poise. He looked under control, delivery-wise, he didn't overthrow the ball.”

Mariners manager Scott Servais said, “Give their young guy credit. Sometimes, rookies making their first Major League appearance will come out there a little jittery. He did not. He went right after it and attacked the strike zone and was really aggressive with a good fastball that was down for the most part, and a decent breaking ball.”

Castellani admitted nerves, even though the pandemic meant he pitched in front of cutouts instead of humans.

“I mean, I was in Fall League last year, so I’m kind of used to playing with no fans,” Castellani quipped.

Black said he would have let Castellani work through the fifth if he wasn’t giving up any hits. But Black knew the intrasquad games and bullpen sessions were enough to expect much more.

Hoffman rescued the start by working Evan White into a double-play grounder and Tim Lopes into a chop to the mound, to begin the relief effort. Crawford’s two-out single off Hoffman in the sixth stood between the Rockies and the second no-hitter in their history. Ubaldo Jiménez’s gem against the Braves on April 17, 2010, stands as the Rockies’ only no-no.

Of the club’s one-hitters, five have been combined. The only complete-game one-hitter came last year, from Germán Márquez against the Giants on April 14.