PHOENIX >> It’s a brand new day in the major leagues — potentially an even brighter one for base-stealers like Trea Turner and Ronald Acuña Jr., and most definitely a change of pace for veteran aces like Gerrit Cole or Yu Darvish.

The bases are bigger, and the pickoff rules are different. The pitch clock has arrived, and infield shifts are gone.

Sorry, Shohei Ohtani, you took too long to throw that pitch. Bryce Harper, get back in the batter’s box. Xander Bogaerts, can’t stand there when Mookie Betts is hitting.

Only one thing is certain to stay the same: Everyone will try to find an edge, aiming to take advantage of baseball’s dramatic alterations.

“I think the one thing we know about our industry is to the extent there’s an advantage to be gained, every team is going to be doing everything possible to try to exploit that advantage to the best of its ability,” said Chris Antonetti, president of baseball operations for the Cleveland Guardians.

Those are the conversations that are dominating spring training this year after Major League Baseball approved a series of changes in September in an effort to make the sport more appealing to a younger generation turned off by its lack of action and leisurely tempo.

As players reported to camps in Florida and Arizona to ramp up their preparation for the season, Commissioner Rob Manfred expressed confidence that the changes would work — after what could be an occasionally bumpy transition period.

“I think you’re going to see a game that moves along with more pace,” Manfred said. “I think you’re going to see more balls in play. I think that you’re going to look at the field and see players positioned the way that most of us grew up seeing them positioned. And I really think that (you’re) going to see a movement toward the very best form of our game.”

The size of the bases has been increased to 18-inch squares from 15. The new pitch clock is 15 seconds with no runners on base and 20 seconds with runners. The increasingly frequent infield shift has been eliminated, and there is a limit of two of what MLB calls disengagements — pickoff attempts or steps off the rubber — per plate appearance.

“I think the pitch clock will be the most impactful for sure,” Milwaukee Brewers manager Craig Counsell said. “I mean I’m hoping that’s the one that’s most impactful. I hope fans notice a real improvement in the pace of the game.”

The pitch clock helped reduce the average time of a nine-inning game in the minor leagues from 3 hours, 4 minutes in 2021 to 2:38 last season. A catcher is required to be in the catcher’s box with nine seconds left on the clock and a hitter in the batter’s box and focused on the pitcher with eight seconds remaining.

Penalties for violations will be a ball called against a pitcher and a strike called against a batter. And there almost assuredly will be some violations through the start of the season as players get used to the clock.

“I’m not worried about it,” Chicago White Sox pitcher Lance Lynn said. “The hitters are going to hate it.”

Under the new rules on defensive positioning, two infielders will be required to be on either side of second and all infielders to be within the outer boundary of the infield when the pitcher is on the rubber. Infielders may not switch sides unless there is a substitution, but five-man infields will still be allowed.

With the elimination of the shift, major league teams could get more creative with their outfielders. It’s not hard to imagine a late-game scenario where a corner outfielder could move into a spot that a shifted infielder used to fill.

“At least for my lifetime, when a ball’s hit in a certain spot, you feel like, at least when you’re watching on TV, you feel like it’s a hit and you look up and somebody’s standing there,” San Diego Padres general manager A.J. Preller said.

“So I think that’ll probably take some getting used to, kind of seeing that shift back, and from a strategy standpoint, how that plays out.”

The bigger bases are intended to help reduce injuries and increase stolen bases — due to their size, the bases are closer together by a few inches. There were 3,297 steal attempts in the majors last year, according to Sportradar, up from 2,926 in 2021 but a marked decrease compared with 4,365 attempts a decade ago in 2012.

All those bang-bang plays on the bases just got a little more interesting.

But the most intriguing change just might be the limit on disengagements. A balk is called for a third step off or pickoff unless there is an out, and the limit is reset if a runner advances.

What pitchers do with their disengagements — which ones keep one in their back pocket, which ones use all of them and which ones are willing to risk a balk with a throw over — will be closely scouted at the start of the season as teams look for a base- running edge.

“There’s a lot of gamesmanship here,” Chicago Cubs general manager Carter Hawkins said. “So try to figure out how to best play it. I’m sure there’ll be some cat-and-mouse games going on, and different pitchers will come up with different plans that we’ll have to adjust to, and baserunners as well.

“I think that’s exciting to be able to watch and some chances for some competitive advantages.”