If it wasn’t official already, the news that broke Wednesday of the Twins calling up slugger Miguel Sano makes it so: This is the summer the organization went at least most of the way in on a youth movement.

This also is the summer that the Twins and their fans will relearn a difficult truth: It often takes a while for prospects to pan out, even if they are as highly regarded as many of the ones the Twins to whom the Twins are giving chances.

The season began with high hopes that three young hitters who showed promise in 2014 — Danny Santana, Kennys Vargas and Oswaldo Arcia — could make progress and become mainstays in the lineup.

All three have struggled enough that they have spent time back in the minors. A fourth prospect, Aaron Hicks, still can’t claim a job.

Pitcher Trevor May made his debut in 2014 and has held down a spot in the 2015 rotation by pitching adequately while given a chance. But he could be the odd man out when Ervin Santana returns this weekend. Alex Meyer came up recently and has a 16.87 ERA in two games.

Byron Buxton, the biggest call-up and prospect of them all, was hitting .189 in 37 at-bats after his much anticipated promotion. He’s now on the disabled list.

Sano will get the next shot, and he’ll probably have some flashes of massive power in between long stretches of flailing.

All of this is OK. All of this is supposed to happen. Hardly anyone has sustained success immediately.

If you think of the actual homegrown mainstays in the Twins’ lineup and on their pitching staff, there is a nearly universal theme of early struggle.

Brian Dozier was a rough-around-the-edges shortstop for the 2012 Twins, finding himself back in Class AAA Rochester that season before reinventing himself as a second baseman.

Trevor Plouffe was a subpar defensive third baseman and a one-trick pony at the plate who needed years of refinement to become an above-average fielder and hitter.

Torii Hunter (yes, he counts) used to routinely miss sliders by three feet. Kyle Gibson was a mess in 2013, was better last year and is reliable now. Glen Perkins almost pitched his way out of the organization before finding his niche as a reliever.

Joe Mauer? He looked like he belonged from the jump. But there aren’t many Mauers, regardless of what you think of him now.

The Sano call-up is fun. The Buxton call-up was fun. When both are presumably healthy and playing together at Target Field later this summer, their flashes of brilliance will be a blast.

Just remember that it’s a process. And the real fun will be when/if this wave of young talent starts to figure everything out and is here for good.

Michael Rand