The Cubs can use hitting jargon to explain Jason Heyward's steep offensive decline, focusing on bat angle and launch position, but there's still a bottom-line aspect to his struggles: How to handle the pressure that comes with signing the biggest contract in franchise history.

"You try so hard – and you want to be so good – you get to a point where you can't breathe," hitting coach John Mallee said.

If Heyward's life forever changed 13-plus months ago when he turned down the St. Louis Cardinals and signed that eight-year, $184 million megadeal, those mechanical issues had already been building for someone with long arms, a 6-foot-5-inch frame, a high-maintenance swing and a history of starting slow.

To his credit, it didn't stop Heyward from winning his fourth Gold Glove or setting an example for a young lineup with his patient approach at the plate and aggressive instincts on the bases. Even as manager Joe Maddon turned him into a part-time outfielder during the postseason, Heyward didn't sulk or drift off, calling a players-only meeting during the Game 7 rain delay in the World Series.

Sometime after the championship parade down Lake Shore Drive and Michigan Avenue, Heyward moved to Arizona, to be near the team's Mesa complex and break down his swing so it could be rebuilt again. The reboot is underway, which will again make Heyward one of the most closely watched players in February, even on a team loaded with stars.

"Being the player he is and the human being that he is and the teammate that he is," Mallee said, "he really put a lot of stress on himself, in my opinion, trying to be successful for the Cubs and for his teammates.

"You get to a point where you really just can't find yourself. You got to take a step back, take a breather and take the offseason and assess what went wrong. And then figure out where you were good, because he's one of the best guys in baseball and we just lost him (by) a hair there."

The Cubs studied what Heyward did with the Atlanta Braves in 2012, when he generated 27 homers and 82 RBI and looked like a budding superstar during his age-22 season. Heyward has been working closely in Mesa with assistant hitting coach Eric Hinske, who has a unique understanding after playing on that 2012 Braves team.

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While the spring-training coverage will focus on Heyward 2.0, Mallee insisted this isn't a dramatic overhaul, changing the position of his hands, holding the bat more straight up instead of tilted behind his head and getting into more of a ready position.

"Sometimes things creep into your swing that you don't even recognize," Mallee said. "He's trying to mirror the swing that he had then.

"It's not actually making a change – it's just getting him to who he was. Those are all natural moves for him. Those are all moves that he's done in the past before. So it's not like adding a leg kick to somebody – or trying to teach him to pull the ball more or anything like that. It's just getting him back to the swing patterns that he had when he had success."

As much as anything, Theo Epstein's front office invested in Heyward's age (now 27), athleticism and intangibles. Of course, the Cubs expected more production than seven homers and a .631 OPS that ranked 144th out of the 146 qualified big-league hitters last season. But if Heyward bombed in Year 1, it's not like it automatically meant a sunk cost or the beginning of the end.

Mallee also wrote off some of this as bad luck, saying Heyward "was shifted more than he's ever been shifted in his career" and pointing to a .266 batting average on balls in play. But the same logic that drove the Heyward decision – and helped the franchise win its first World Series title in 108 years – now makes team officials believe his offensive game can be salvaged.

"Everybody knows he didn't have a great year hitting," bench coach Dave Martinez said. "But what this guy brought every day to our clubhouse – irreplaceable."

Maddon again compared Heyward to Jon Lester, who admittedly felt the weight of his $155 million megadeal in April 2015 and needed an adjustment period before becoming a Cy Young Award finalist last year, even after spending almost his entire career in a high-pressure environment with the Boston Red Sox.

"Of course, it's difficult," Maddon said. "You saw it with Jon Lester the year before, what he did last year compared to the previous year. Jason's been working very hard. They really like a lot of the adjustments that he's been making already.

"Listen, I just love the way Jason plays, regardless. I said that all last year. I do believe you're going to see an increase in offense, all around, whether it's hitting for average, power, RBIs, runs scored, the whole thing. But I just really am a big fan of his as a baseball player.

"A year older and a year wiser with a lot of really good offseason work – and it's been properly directed – I think you're going to see a nice uptick this year."

With so much young talent and cheap labor in their lineup, the Cubs could afford a down season from Heyward, before the salaries for Kris Bryant, Addison Russell, Kyle Schwarber and Javier Baez soar in the coming years.

Being a member of the supporting cast – and not having to be The Man all the time – was part of the attraction to playing at Wrigley Field. Heyward will always be part of The Team, but the Cubs will need more if they want to become a dynasty.

"Just get back to doing things simple, the right way," Heyward said. "(It's) being in a good position to hit all the time. It's easier said than done when you're trying to do it in the season, working in the cage and (then) trying to go compete to help a team win. The offseason really allows you to slow things down (and) take time to focus on all the little things and over-exaggerate that."