ST. PETERSBURG -- Xavier Isaac has heard the comparisons before. He’s a big, powerful left-handed hitter. He’s listed at 6-foot-4 and 240 pounds. He possesses elite raw power, can hit for average and plays first base. He could do a lot worse than becoming a player like longtime Phillies first baseman Ryan Howard, right?

But that’s not what Isaac, the first-round Draft pick who signed with the Rays on Friday, is setting out to do as he begins his professional career.

“I don’t really think about that,” Isaac said Friday afternoon at Tropicana Field, wearing a white No. 22 Rays jersey with his name on the back. “I want to be Xavier Isaac, and I want everybody to know I’m Xavier Isaac.”

Some Draft analysts and media immediately labeled Tampa Bay’s first-round pick as risky at best and a reach at worst, calling into question the idea of selecting a high school first baseman that early, especially one who missed key opportunities against top-tier pitching last summer due to a stress fracture in his foot. And it was out of character for the Rays, who had taken a first baseman in the first round only once before.

But the Rays believed in Isaac, and Isaac believes in himself.

“It motivates me a lot. The Rays had the trust in me,” Isaac said. “Like they said, they don’t follow the board. They trust me, so they got me. I’m gonna grind and I’m gonna show everybody why I’m a first-rounder.”

Isaac’s confidence stood out nearly as much as his physical presence on Friday, when he officially signed his contract and received a $2,548,900 bonus, the full slot value for the 29th overall pick. His work ethic and determination shined through, too, even as he met with reporters near the home dugout at Tropicana Field.

“Obviously, the way this last summer and fall worked out, maybe he didn't have as much of a spotlight on him from a Draft perspective or from a media perspective,” Rays senior director of amateur scouting Rob Metzler said. “And I think that he's incredibly focused on showing that he's one of the best players in this Draft class. We're excited to have him do it in our uniform.”

For the Rays, there was little doubt about the pick. They put in a lot of hours evaluating Isaac, including a workout at Durham Bulls Athletic Park -- home of their Triple-A affiliate -- in late May and a Zoom call three days before the Draft. They saw him bounce back from his injury last year and show his skills this spring.

If they didn’t take him at the end of the first round, they expected, he’d have been off the board by the time they were back on the clock with the 65th selection. And they believe the 18-year-old has enormous potential, in the field and especially at the plate.

“We think he's more than capable. We like his hands. We like his feet. We think he's gonna be a good first baseman,” Metzler said. “We really like Xavier's bat. It's not just about power. He can hit, hit to all fields. We think he's a hitter first with tremendous power, so we're excited to see it in action.”

First, Isaac was able to celebrate and enjoy Friday at Tropicana Field. He toured the ballpark with his mother and father, Theresa and Ike, as well as his grandmother, Mary, and 7-year-old brother, Xander, and his representatives. He stayed for the Rays’ game against the Guardians.

On Saturday, his journey will begin. After forgoing his commitment to the University of Florida, where he’d been taking “Summer B” classes, Isaac will report to the Rays’ facility in Port Charlotte, Fla. He’ll likely get 40-50 at-bats in the Rookie-level Florida Complex League this summer, as 2021 first-rounder Carson Williams did last season.

Now, it’s time to prove the Rays -- and himself -- right.

“I like how they took the chance on me,” Isaac said, “and I’m gonna prove I’m one of the best first basemen ever.”