CLEARWATER, Fla. -- Robert Stock had been released by three major-league clubs and spent the previous season pitching for an independent team in North Jersey when spring training began with him at home.

A decade earlier, he was one of the nation’s premier high-school players. But Stock never reached the majors. And in February of 2017, baseball seemed set to move on without him.

For Stock, there was one thing left to do: go viral. He spent the winter throwing as hard as he could, tracking his speed with a radar gun he purchased as a teenager, and strengthening his mechanics. Surely, Stock thought, a major-league team would want a pitcher armed with a 98 mph fastball.

“I felt pretty confident that what I had been doing warranted some interest,” said Stock, who is keeping his dream alive this spring with the Phillies at age 30.

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Needing a way to generate interest for his improved fastball, Stock grabbed a camera and went to a public park in Scottsdale, Ariz., with his wife Sara serving as his videographer. The right-hander fired seven fastballs against a net, topping out at 98.8 mph.

Stock uploaded the video -- titled “Another day in the literal park with Robert Stock” -- to YouTube and posted it to a Facebook group of former pro players, hoping one of them would know someone who would want to sign him. Four teams called the next day and the Reds invited him to their Arizona spring-training facility, just miles from the public park where Stock filmed his video.

“They have one spring-training field that’s immediately outside the clubhouse. Even the manager was watching,” Stock said. “Just some random dude that they might sign in a nameless minor-league transaction.”

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Stock joined the Reds and was pitching two months later in the minor leagues. The video worked. His career, promising enough in 2005 for Baseball America to name him the nation’s top youth baseball player, was back on track.

“I’ve been lucky enough that when I was younger in high school and college, I played with all of these guys who are now MLB All-Stars,” Stock said. “Knowing that at one point in my life I was right there with all of these players, I had the belief that I could continue playing. I just had to figure it out a way to be back on the same fields.”

Stock was drafted as a catcher by St. Louis in 2009’s second round, but the Cardinals transitioned him three years later to the mound. He pitched in college at Southern California, where he began his career as a 16-year-old freshman. His fastball as a Cardinals minor-leaguer sat in the low-90s and the transition fizzled. St. Louis released him in 2014. Houston released him in 2015, three weeks after signing him. And Pittsburgh released him later that year.

“It was terrible,” Stock said of moving from catcher to pitcher. “I had two weeks of practice before I went to a full-season squad. The very first inning I pitched, I gave up a grand slam. It was really bad for years.”

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The only team with any interest for 2016 was the independent New Jersey Jackals, who also signed Stock’s younger brother to be their catcher. Stock pitched well that summer in Passaic County, but interest that winter was just as tepid as it had been a year earlier. Then he uploaded the YouTube video.

Stock finished 2017 with Cincinnati’s double-A team, finding success with his new fastball. He filmed another video after the season at his high-school field, capturing the first time his fastball reached triple-digits. Stock started 2018 in San Diego’s camp and reached the majors that June, 16 months after the viral video revived his career.

“It’s the belief in a process for improvement,” Stock said. “If you see improvement in yourself, it’s just a function of the rate of improvement to time. You keep putting in more time if your process makes you better.”

“It’s whole-body strength,” Stock said. “It’s legs and arms. When you say strength, it’s not necessarily, ‘Well, how much can you bench press?’ The strength to maintain proper positions, like good forms. It takes a lot of strength to move in the right position.”

Stock had a 2.50 ERA with the Padres in 32 appearances in 2018 and made the team’s opening-day roster in 2019 before his season was plagued by arm troubles that limited him to 10 2/3 innings. The Phillies claimed him off waivers last October, hoping his powerful fastball can give a boost to their thin bullpen.

Stock is one of three relievers the Phillies claimed this winter and joins a spring roster that features six veteran relievers signed to minor-league deals. The Phillies did not invest much financial capital into their bullpen, hoping instead to find value with pitchers like Stock.

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Stock has thrown 500 major-league fastballs over the last two seasons, with an average speed of more than 98 mph. The video he posted in February of 2017 has been viewed more than 52,000 times. Stock’s velocity is just as strong as it was when his career was on the brink, but his wife no longer needs to hold the camera.

“If I step far enough away to look at it, it can be gratifying,” Stock said of saving his career. “But you’re never satisfied. You can always look at ways to improve. I’m never just sitting at home saying, ‘You know what? I made it to the major leagues. That’s good enough.’”

Extra bases

Nick Pivetta will start Saturday’s Grapefruit League opener against Detroit in Lakeland, Fla. Aaron Nola will start Sunday at home against Pittsburgh and Vince Velasquez will start Monday in Clearwater vs. Baltimore.