This is the year of the prospect across Major League Baseball, and the Twins are one of the teams leading the charge.

Their wave of youth — including the big four of Eddie Rosario, Byron Buxton, Alex Meyer and Miguel Sano — has finally hit Target Field. All have shown why they were top prospects — but there also have been some things to be concerned about.

Here are some observations on these four talented players, in order of major league debut:

Eddie Rosario, OF

Rosario can drive a baseball, as he hit the first major league pitch he saw for a home run. And manager Paul Molitor trusts him against lefthanded and righthanded pitchers. The coaching staff is impressed with his ability to make adjustments, but Rosario chases too many pitches and is striking out nearly once a game. Defensively, his arm and range have been a boost.

Byron Buxton, OF

What a rough beginning. Buxton batted .189 in 11 games before a sprained ligament in his thumb landed him on the disabled list. He fell behind in the count frequently as he adjusted to better pitching.

He can fly, but his 78 percent stolen base rate in the minors was on speed more that savvy, and the coaching staff has worked with him on getting better jumps.

And his thumb injury could have been prevented. Someone should have been on him about holding his batting gloves in his hands when he dives into bases — which protects the fingers and thumb. Or he could wear the same sliding mitten that Brian Dozier wears.

Alex Meyer, P

The big righthander also had a rough debut — giving up five earned runs in 2 ⅔ innings before being sent back to Class AAA Rochester.

He doesn’t stand tall in his delivery, and a scout told me he pitches like he’s 6-4 instead of 6-9. His pitches are flat. The Twins have seen this and have given him drills to raise his release point and get a downward angle. But the real adjustment has to come during the offseason.

Miguel Sano, DH-3B

The quality of Sano’s at-bats has surprised many. Monday, for example, he saw 22 pitches over four at-bats. He has been aggressive when he sees a pitch he likes, and has fought back when down in the count to draw walks. He has one home run but looks every bit like the power bat the Twins need.

The Twins have Sano working out at first base and plan to mix in some outfield work, too. That’s fine, but that should have happened as he moved through the system. He shouldn’t have to learn new positions while he’s learning how to hit in the majors. But, hey, his bat hasn’t been the problem so far.

Central Intelligence

Jeff Samardzija is either auditioning for new teams or trying to convince the White Sox to not blow up the team at the trade deadline. He shut down a dangerous Blue Jays team on Thursday with about 12 scouts in attendance. He has a 2.40 ERA over his past six starts.

• • •

Jarrod Dyson made Royals fans forget about the loss of Alex Gordon for one day Thursday when he made an over-the-shoulder grab of Grady Sizemore’s drive. Dyson and Paulo Orlando will get time while Gordon misses two months because of a groin strain suffered Wednesday.

• • •

The Twins will see an improved Shane Greene on Sunday when he is called up to start for the Tigers. Greene went to Class AAA Toledo with orders to use his changeup more, and he posted a 3.42 ERA in five starts for the Mud Hens.

• • •

Now that Cody Anderson has solidified the Indians rotation, the team looks ready to take off. The first four starters — Corey Kluber, Trevor Bauer, Carlos Carrasco and Danny Salazar — are all over 100 strikeouts before the All-Star break — a major league first for one staff, according to STATS.

Three observations ...

• It will be interesting to see just how the Phillies blow up their roster over the next few weeks. Cole Hamels, Jonathan Papelbon, Ben Revere, Ryan Howard and others could be traded.

• Former Twins outfielder Delmon Young, released by Baltimore last week, is in danger of having his run of six straight postseason appearances — which leads active players — come to an end.

•  Outfielder Cameron Maybin, whom the Padres insisted the Braves take as part of the Melvin Upton Jr. trade, has been one of the pleasant surprises in the league.

... and two predictions

• Cincinnati’s Todd Frazier will win the Home Run Derby, beating Baltimore’s Manny Machado in the finals.

• The American League will win the All-Star Game for the third consecutive year, beating the National League 6-2.