With Trout out of the running, Pujols will compete against Kris Bryant and Anthony Rizzo of the Cubs, Todd Frazier of the Reds, Josh Donaldson of the Blue Jays, Manny Machado of the Orioles, Joc Pederson of the Dodgers and Prince Fielder of the Rangers.
The Derby, slated for July 13 at Great American Ball Park in Cincinnati, has turned into a bracket-style competition this year. Eight players will take part in a single-elimination tournament where each batter has five minutes to hit as many home runs as possible, though extra time can be earned based on distances.
Pujols is the No. 1 seed, by virtue of his American League-leading 26 home runs, and will begin by competing against Bryant.
Trout will be on the field, as a spectator.
"It's one of the things I liked to watch growing up," Trout said. "I just want to see Albert win it, and we'll go from there."
Trout ranked second in fan votes for the All-Star Game presented by T-Mobile and was mentioned more times than anybody on the player ballot. He's the reigning AL Most Valuable Player, the game's biggest star and perhaps the one guy Major League Baseball would love to see compete in one of its jewel events.
Trout was torn.
"I was thinking about it," he said of doing his first Derby. "I have my mind set on one thing, and then I'd come to the field and other people would try to persuade me."
Friends back in New Jersey were pushing Trout to do it; even Pujols himself tried to convince him, as he has in years past.
Angels manager Mike Scioscia has previously said he doesn't like seeing his players take part in the Derby because he believes the workload is too exhaustive, though he ultimately leaves it up to his players. Trout said he didn't even speak to Scioscia about his decision this year.
"It's his decision," Scioscia said of Trout. "I know they've adjusted some things, and I know they're going to continue to tweak it so it's not as demanding on each contestant, but I think he'd be fine."
Trout -- the Major League leader in Wins Above Replacement from 2012-14 -- ranks fifth in the Majors with 24 home runs, while adding a .305/.400/.604 slash line. His exit velocity on batted balls, 117.71 mph, is third-highest in baseball, according to Statcast™.
Someday, he'll put those talents on display in the Home Run Derby.