Chris Sale tells reporters he's learned from his mistake of cutting his White Sox jersey and has a good reason for why he's confident it won't happen again in Boston. (0:49)

FORT MYERS, Fla. -- There's no denying Chris Sale is entering a new phase of his career this season, but it isn't for the reason you would think.

For the first time as a big league pitcher, Sale won't be working with Don Cooper.

Cooper, 60, has been the Chicago White Sox's pitching coach since 2002, which means he has overseen each of the 17,271 pitches Sale has thrown since his major league debut in 2010. He helped ease Sale's transition from the bullpen to the starting rotation in 2012, coaxed the ace lefty through five All-Star seasons and even convinced him to change his style of pitching last year.

Because Sale spent only one month in the minors after being drafted in 2010, Cooper is practically the only coach he has ever had as a professional. When Sale gets into a jam on the mound, Cooper's voice usually is the one he hears in his head. They grew so close over the years that they practically finished one another's sentences.

"Coop knows me better than I know myself," Sale said Tuesday.

Following his trade from Chicago, Chris Sale leaves behind the only pitching coach he's ever had as a pro. Can he forge the same sort of bonds in Boston? Jasen Vinlove/USA Today Sports

And so, as he settles into spring training with the Boston Red Sox after a blockbuster trade two months ago, Sale's biggest immediate challenge will be developing a rapport with Boston pitching coach Carl Willis, director of pitching development Brian Bannister and even manager John Farrell, a former pitching coach.

That process figures to be easier for Sale than it would be for a younger pitcher with a less impressive track record. But Cooper's influence on Sale can't be minimized. Just last spring, for example, Cooper helped Sale transform from a strikeout-obsessed thrower into a more well-rounded pitcher.

The differences were stark. Sale's average fastball velocity dipped to 92.7 mph last season, down from 94.4 mph in 2015, according to ESPN Stats & Information. He also threw fewer changeups (15.7 percent compared to 27.7 percent in 2015) and more sliders (24.9 percent compared to 19.8 percent in 2015).

The idea: Pitch to contact and get quicker outs in order to go deeper into games rather than always aiming for strikeouts. It worked. Sale struck out 9.3 batters per nine innings, down from 10.8 in 2014 and 11.8 in 2015, but he led the majors with six complete games and logged a career-high 226 2/3 innings, all while posting a 3.34 ERA that represented a slight improvement from his 3.41 mark in 2015.

"It was more [about] making smarter pitches in smarter situations," Sale said. "I got to a point a few years ago where I was just becoming a thrower. It was [about] working smarter instead of harder."

Heeding Don Cooper's advice, Chris Sale began pitching to contact more in 2016. The result? He threw six complete games and a career-high 226 2/3 innings. Ted S. Warren/AP Photo

Cooper was able to sell Sale on the merits of making that adjustment because of their longstanding relationship. The Red Sox's pitching gurus likely will have to earn Sale's trust.

"That's my responsibility, my job, to learn his language, not for him to learn mine," Willis said. "It's about Chris Sale being comfortable. I will take the time to learn. He and I discussed some things during the winter as far as how I go about things and my style of coaching. Not to compare myself with Coop, but our way of doing things is similar, from what I've gathered from Chris, so hopefully it'll allow him to get comfortable right away."

Indeed, Willis has a strong track record with veteran pitchers. He has coached four Cy Young Award winners, from CC Sabathia (2007) and Cliff Lee (2008) with the Cleveland Indians to Felix Hernandez (2010) with the Seattle Mariners and Red Sox right-hander Rick Porcello last season.

But after so many years with Cooper, hearing new voices in his ear nevertheless will be another adjustment for Sale, who is attempting to avoid the pitfalls that befell Josh Beckett, John Lackey, Porcello, David Price and other pitchers in their first seasons in Boston.

"The more you're around people, the better your relationship becomes," Sale said. "You learn them, they learn you and vice versa. You just bounce ideas off each other. It's not going to be perfect the first time -- maybe it will, I don't know -- but some of those things we'll figure out along the way."

It's all part of Sale's next chapter.