DENVER — The Boston Red Sox selected Eastlake High (Calif.) shortstop Marcelo Mayer with the fourth overall pick in the MLB draft.

The Pirates drafted University of Louisville catcher Henry Davis with the No. 1 overall pick. Texas, picking second, went with Vanderbilt pitcher Jack Leiter. Detroit selected high school pitcher Jackson Jobe with the No. 3 pick.

Mayer was rated as the No. 1 draft prospect by MLB.com and the No. 2 prospect by Baseball America.

According to his MLB Pipeline scouting report, “He has average or above tools across the board, starting with a plus feel to hit from the left side of the plate. He has an advanced approach and knowledge of the strike zone to go with elite bat-to-ball skills and a pure stroke. Long and lean, there’s a lot of raw power for him to grow into, with some scouts seeing a Corey Seager-like offensive profile if it all comes together.”

Mayer hit 14 homers his senior year, one shy of the school record set by 2000 No. 1 pick Adrian Gonzalez. Marcelo batted .392 with 45 RBI and 46 runs.

“I did see it coming,” Mayer said of his slide to the Red Sox. “I knew they were high on me. I’m just super blessed to be part of the organization.”

The Red Sox have drafted in the top five only three other times. They picked third overall in 1967 (Mike Garman), fourth overall in 1966 (Ken Brett) and fifth in 1965 (Billy Conigliaro).

“I think we all view it as a tremendous opportunity,” Red Sox director of amateur scouting Paul Toboni said this past week about drafting fourth overall. “I think we want to draft a kid that really sets the tone for the rest of the minor leaguers and eventually his teammates in the big leagues. That’s with his work ethic, with his competitiveness, his love for the game and just his overall character. It’s not every year, it’s not every 10 years for us, you can access a talent like this, in this area of the draft.”

Davis, the No. 1 overall pick, has big power and an even bigger arm, throwing out 46% of would-be basestealers to become a finalist for the Buster Posey Award as college baseball’s best defensive catcher.

He batted .370, led the Cardinals with 15 homers, and his .482 on-base percentage was best in the Atlantic Coast Conference.

“I want to win, a competitor,” Davis said. “I’m going to do everything I can to help this organization get where it needs to be.”

The Rangers grabbed Leiter with the second pick, landing a right-hander with a mid-90s fastball and two overpowering breaking pitches.

Leiter is the son of former big league All-Star pitcher Al Leiter. He has a repertoire that could play near the top of a big league rotation. He was 11-4 with a 2.13 ERA this season with the Commodores, including a no-hitter against South Carolina, and struck out 179 in 110 innings.