New Jersey high school left-handed pitcher Jason Groome was once considered the possible No. 1 pick in the major league draft.

But Groome fell to the Boston Red Sox, with the 12th overall pick, in the opening round of the draft Thursday night.

Jason Groome pitches during the Perfect Game All-American Classic high school baseball game on Aug. 16, 2015, in San Diego. Groome was chosen 12th overall by the Red Sox on Thursday.

In the second round, Boston selected Florida Atlantic University shortstop C.J. Chatham.

Speculation on why Groome’s stock fell is varied, with possible extreme salary demands being one of them.

As the 12th overall pick, Groome would be slotted to receive about $3 million. His agent reportedly is asking for $4 million.

Groome had a scholarship offer from Vanderbilt but reportedly was leaning toward a junior college, which would allow him to re-enter the draft in 2017 if he doesn’t sign this year.

But in a conference call with New Jersey media Thursday, Groome said, “Money doesn’t really matter to me. I’m just happy to start the next chapter of my life and that’s professional baseball.”

Groome, 6-foot-6, 220 pounds, is said to have a mid-90s fastball with a superb curveball.

“He’s got really good stuff,” said Mike Rikard, the Red Sox director of amateur scouting. “He’s really advanced. He has a big fastball and a good curveball, and he can throw his change-up for strikes.

“He’s a big, durable guy. He has a nice easy delivery. And he’s a strike thrower.”

Concerning the ability to sign him, Rikard said, “We’re hopeful. We haven’t gotten into that a lot at this point.”

The Philadelphia Phillies had the first overall pick and selected high school outfielder Mickey Moniak from San Diego County, California. Moniak, 18, is considered a five-tool prospect. The Cincinnati Reds followed by taking University of Tennessee third baseman Nick Senzel, who batted .352/1.051 OPS.

The rest of the top 10 picks included high school pitcher Ian Anderson (Braves) at No. 3; high school pitcher Riley Pint (Rockies) fourth; University of Louisville outfielder Corey Ray (Brewers) fifth; University of Florida pitcher A.J. Puk (A’s) sixth; high school pitcher Braxton Garrett (Marlins) seventh; Stanford pitcher Cal Quantrill (Padres) eighth; high school pitcher Matt Manning (Tigers) ninth and University of Miami catcher Zack Collins (White Sox) 10th.

With the 11th pick, Seattle chose Mercer outfielder Kyle Lewis.

There was speculation that the Red Sox would go for Boston College pitcher Justin Dunn (he went to the Mets with the 19th pick), but Boston could not resist Groome’s potential.