FORT MYERS — David Price takes a deep breath and his eyes zero in on the target. To look at the Red Sox left-hander in that moment through a close-up TV shot is to wonder whether he would hear an overhead sonic boom.

The nurturing roots of the phenomenal focus Price brings to the mound at Fenway Park can be traced to a customer at a bookstore close to Major League Baseball’s oldest yard two decades ago.

“I remember it like it was yesterday,” Brian Cain, based in Paradise Valley, Ariz., said by phone. “July 4, 2000. I walked into a Barnes and Noble right by Fenway, on Boylston Street, and for some reason Ken Ravizza’s book, ‘Heads-Up Baseball’ stood out to me. I picked it out and almost read it cover to cover right there in the store. That one book changed my entire life.”

So much so that Cain, a native of Williamstown and a former University of Vermont baseball player, studied the art of mental performance mastery under Ravizza at Cal State Fullerton, received a master’s degree, and entered the sports psychology field.

Cain met Price when brought to Vanderbilt University by baseball coach Tom Corbin to work with the team. During his time with the Tampa Bay Rays, Price worked extensively with Cain’s late mentor, Ravizza, brought to the organization by then manager Joe Maddon.

And the rest is laser-focus history. When Ravizza, who died last July, made presentations at colleges and high schools and talked about the connection between a deep breath and improved focus, he used videos of Price to demonstrate his point.

“He was a really special man, someone I talked to a lot whenever I was in Tampa. The deep breath was something he would always preach,” Price said on Tuesday of Ravizza. “I don’t have to even think about it anymore. It’s something I always do. Bring my shoulders up and let them sink back out. Whenever I do that, it allows me to forget about whatever just happened and to be able to focus in on that pitch right there.”

Price credited Cain and Ravizza by name for giving him the tools he uses to focus.

“It’s allowed me to move forward, whether it’s during the game or right after a pitch or after a start or after a bad string of starts,” Price said. “It’s something that can center me into what I’m trying to do right now.”

For Price, 33, concentration is one of the skills that has enabled him to compile a rare career strikeout-walk ratio of 3.7-to-1.

“I’ve had a chance to work with more than 700 guys drafted into professional baseball, 70 drafted in the first round,” Cain said. “If I had to pick out one guy as a model from an attitude, effort, focus, work-ethic standpoint, it would be David Price. That guy’s commitment from the day I met him was noticeably different from everybody else, and I’m talking about everybody.”

Cain explained the benefit of a deep breath at the end of a pre-pitch routine that includes visualizing the location of the upcoming pitch.

“Physiologically, when you take a deep breath, not to get too scientific, it’s going to oxygenate the brain,” Cain said. “It’s going to allow you to have more clarity of thought. It’s going to decrease the heart rate. With that quieting of the mind, it’s going to allow you to be more present and focused on that next pitch that you’re trying to execute because that next pitch is all that matters.”

Cain described the pre-pitch routine in general and the breath in particular that he also taught to, among others, Cy Young winner Jake Arrieta, as, “a way to quiet your mind, commit to the pitch and just be present and be where your feet are.”

When Price’s left foot was on the rubber during the World Series vs. the Dodgers, he went 2-0 with a 1.98 ERA in two starts and a bullpen appearance.