SAN FRANCISCO -- The Giants never talked of rebuilding in 2019, preferring instead to put the focus on being competitive as long as possible. But if you asked team officials for their true feelings, the sense was always that this past season was a transition year to 2020 and beyond.

In that respect, there might not have been a greater development over the course of the season than the emergence of outfielder Mike Yastrzemski. He can be Farhan Zaidi's Northern California version of Chris Taylor or Max Muncy, older prospects who also flourished when given the opportunity to prove that they were everyday big leaguers.

Yastrzemski isn't looking at it that way, though.

"I'm trying to take the offseason and understand that there's a lot of work to be done still," Yastrzemski said at the end of his first season. "It's never being satisfied with where you are. You can't take it for granted. It's a time to get healthy and to get stronger and better."

The Giants gladly would take anything more Yastrzemski has to offer because this is a lineup that still has plenty of holes. Yastrzemski was one of just two Giants hitters -- along with Evan Longoria -- to be worth two Wins Above Replacement, per Baseball-Reference. Those also were the only two regulars to finish with an OPS+ that put them above league average as hitters.

Yastrzemski led the Giants in both categories, which is part of the reason why -- despite what he might say about his offseason approach -- he enters the winter as a locked-in member of the lineup. The 28-year-old tied Kevin Pillar for the team lead in homers, becoming just the fifth big leaguer to do so after making his debut in May or later. He joined Pete Alonso, Yordan Alvarez and Fernando Tatis Jr. as the only rookies to hit 21 homers and post a .850 OPS in 2019.

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By any measure, it was a breakthrough, and Yastrzemski never slowed. He got really hot in July and matched his .926 OPS that month with another .926 in August. Yastrzemski finished up with a .848 OPS in September and a .376 on-base percentage that was his highest in any 2019 month.

Yastrzemski said he would take a couple of weeks off to rest his body and mind before getting back at it, and once the work starts, the mindset will be the same as it was in April, when the longtime Orioles prospect was trying to work his way up from Triple-A Sacramento.

"The only things I can control are what I do this offseason, how I approach it, and how I work," he said.