It was Dipoto who finally decided to push that proverbial panic button on April 27, releasing veteran Bobby Abreu and calling up the young Trout -- limited in Spring Training due to a nasty virus and shoulder tendinitis, but off to a surging start at Triple-A Salt Lake -- to help an unproductive offense and bring some life to a team that sorely lacked it.
He probably never envisioned the impact being this great, though.
When Trout arrived, the Angels were getting a .250 on-base percentage from their leadoff spot. Since then, it's gone up to .325. Without Trout, they were 6-14. With him, the Angels -- who had their eight-game winning streak snapped on Wednesday but have finally run their record to .500 -- are 20-12.
Trout isn't solely responsible for the turnaround, of course. Mark Trumbo has been there since Day 1, currently leading the Angels in batting average (.348), OPS (1.029) and homers (10). Pujols has turned it around, hitting seven homers with 14 RBIs over his last 15 games. The starting rotation has pretty much been as good as anticipated, with a collective 3.41 ERA that leads the American League. And the bullpen has stabilized since the acquisition of Ernesto Frieri, dropping its ERA from 4.70 on May 13 to the current 3.57 mark.
But if the Angels end up meeting the expectations they carried into this much-hyped season, it'll be Trout's callup many will point to as the genesis of that resurgence.
And as they currently sit closer to first place than they've been since April 17 -- at 5 1/2 games behind a Rangers team they'll host this weekend -- it's Trout's callup many in his own clubhouse are pointing to as the biggest reason why.
"He's been a huge addition," Trumbo said, "and that's no slight against anybody else."
"He has tangibly brought something that our team desperately needed, and that's on-base percentage from the top of our lineup," Angels manager Mike Scioscia added. "And as the guys in the middle are starting to swing the bats better, you're starting to see some groupings that are starting to flow."
Thanks to somewhat of a loophole in Major League Baseball's roster rules, Trout was able to get 40 games of big league experience last season and still be eligible for the AL Rookie of the Year Award this year.
No doubt, those 40 games helped. A lot.
After struggling through two stints in the big leagues in 2011, with a .220/.281/.390 slash line, Trout has emerged as one of the best young players in baseball. His slash line now is .303/.366/.521. He's already matched his home run (five) and RBI total (16) while stealing twice as many bases (eight) in 10 fewer games. And he ranks in the top five among Major League rookies in basically every offensive category -- batting average, runs, triples, homers, RBIs, on-base percentage and slugging.
"I definitely feel more comfortable, just knowing the guys, knowing the pitchers and just seeing the pitchers," said Trout, who came into the season ranked by MLB.com as the third-best prospect in the Majors. "It's a different experience for me this year."
It's not just the offensive numbers, though.
It's the mind-blowing catches, like when he robbed the Yankees' Nick Swisher of a home run in left field on Tuesday.
"He can absolutely fly," Swisher would say later that night. "If you can't run, you can't get to those balls. Speed is something that you're blessed with, and he's got a whole lot of it."
Or his uncanny discipline in the batter's box, as evidenced by the 4.19 pitches he sees per plate appearance and his overall comfort level hitting with two strikes.
"This is the only 20-year-old I know that has the patience that he has," veteran outfielder Torii Hunter said. "He has plate discipline like no other."
Asked about other young players who were as advanced as Trout is at that age, Scioscia paused, then threw out names like Robin Yount, Ivan Rodriguez, Alan Trammell and Darryl Strawberry. Others have dared compare him to Mickey Mantle. And Hunter's first thoughts were Ken Griffey Jr. and Alex Rodriguez.
Asked about Nationals phenom Bryce Harper, the 19-year-old who's batting .274 with four homers and 11 RBIs through the first 30 games of his first season, Hunter scoffs -- though he may be a bit biased.
"They talk about Harper or whatever. No. This guy," Hunter said of Trout, who he mentors and calls "Little Hunt." "Harper's good. Don't get it twisted. He's good. But this guy, from what I've seen ..."
"I'm not going to compare him to Bryce Harper or anything, but I couldn't imagine him being more skilled at that age," added veteran starter Dan Haren. "The guy can do it all. Coming up at first, I was kind of an outsider, coming from a different organization. He was a little bit cocky, obviously a confident kid, but he's really changed for the better. I mean he handles his business so well in the clubhouse -- even off the field, in the bus, on the plane. He's just really a great kid. He's really been fun to watch kind of grow in these last couple months."
And the Angels have grown right along with him.