The Bronx isn’t the first place Greg Bird wasted no time making a good impression.

During his freshman season at Grandview High School in Aurora, Colo., he spent most of the year with the junior varsity before being called up for a district playoff game.

“Right away, he hit a double off the wall,” said Dean Adams, the recently retired coach at Grandview. “I didn’t put him on varsity at first because we already had a good team and a good catcher. In hindsight, I probably should have.”

That began a standout prep career for the newest Yankee phenom, who hit a pair of homers Wednesday in just his fifth game in the majors.

And Adams never thought of moving Bird down again — a problem he believes the Yankees are about to encounter whenever Mark Teixeira returns from a bone bruise in his lower right leg.

“Good luck sending him down,” Adams said of Bird, who was drafted as a catcher but quickly transitioned in the minors to first base, where he started again in Thursday’s 3-2 loss to the Indians, in which he went o-for-3 with a walk. “He understands the business, but he’s going to make it really hard not to have him play. Obviously, it’s Mark Teixeira, but it’s still going to be hard. And if it wasn’t for Teixeira, I think he’d have been there last year.”

Even so, it’s been a fast progression for the 22-year-old, and Al Pedrique, the manager at Double-A Trenton, who also managed Bird at Class-A Tampa and Charleston, isn’t surprised.

“He was always very professional for someone his age,” Pedrique said. “He got stronger physically and mentally at every level I saw him.”

Pedrique was impressed by Bird’s patience at the plate.

“He never panicked, even if it was 0-2,” Pedrique said. “When people said he took too many pitches, he never changed his approach. He waits until he gets the pitch he wants.”

In some ways, Bird reminded Pedrique of Lyle Overbay, whom Pedrique coached with the Diamondbacks.

The Yankees hope Bird’s ceiling is even higher, and Adams is confident it will be for the former fifth-round pick.

“His mind was always on pro ball,” said Adams, who coached for 26 years, 12 of them at Grandview. “It wasn’t so much a dream as it was an expectation.”

He’s still trying to keep his focus on baseball, trying not to get distracted by the big stage.

“Trying to get used to New York. Took the subway for the first time up here today,” he said. “That was fun. Right now, I’m keeping things as simple as I can so I can focus on what I’m doing on the field.”

Whenever Adams would visit Bird’s parents, who were involved in the school’s booster club, Bird would be in the garage, hitting off a tee.

“I always told people whenever he got to a new level, ‘It’s only a matter of time,’ ” Adams said. “It’s almost like he was groomed for this.”

And it’s a journey that Adams became involved with when Bird was in eighth grade and attended a baseball camp run by Adams.

“I heard the crack of the bat in batting practice, walked over and asked who it was,” Adams said. “Someone said ‘Greg Bird.’ The coach throwing BP tried to get him out, throwing curveballs and sliders and couldn’t do it.”

Even with Bird and Baltimore pitcher Kevin Gausman, Grandview wasn’t able to win a title.

Still, Adams is pleased with how it worked out — except for one thing.

“I talked to him [Wednesday] after he hit the home runs,” Adams said. “I heard they were calling him Birdman and I told him, ‘You’re not Birdman. You’re the Bird Dog.’ Whenever I saw him after he started playing for me, I would say, ‘OK, Bird Dog. Go hunt.’ It’s great to see him doing it up there.”