Major League Baseball made the announcement Monday on its official Twitter page, confirming the return of one of the Derby's most successful hitters.
"It's a really fun event," Alonso told reporters in the Mets clubhouse Monday before their 4-1 win over the Braves in Atlanta. "It's going to be super exciting, so I'm really looking forward to it."
Also before the game, the Braves announced that star outfielder Ronald Acuna Jr. will participate in the Derby. And later Monday, St. Louis Cardinals veteran Albert Pujols entered into the Derby as well, giving the former Los Angeles Dodgers slugger a chance participate in a familiar park.
"It's an honor to be back in the All-Star Game and to have a chance to be part of the Home Run Derby, that's something I enjoy a lot and my kids will have a blast," Pujols said Monday night. "Hopefully, I can put on a good show for them, because at the end of the day, it's not about us, it's about putting a good show for the fans."
Washington Nationalsstar outfielder Juan SotoandPhiladelphia Phillies slugger Kyle Schwarber, who leads the National League in home runs with 28, also will participate in the event, their teams announced Tuesday.Seattle Mariners rookie All-Star outfielder Julio Rodriguez, meanwhile, entered the derby on Wednesday.
Last year, in Denver, Alonso outlasted Baltimore Orioles first baseman Trey Mancini to become the third back-to-back Home Run Derby champion. Alonso recorded 74 home runs -- totaling 6.35 miles in distance -- en route to the crown.
"I think I'm the best power hitter on the planet," Alonso said after the win last year. "Being able to showcase that, and really putting on a fun display for fans, I just think it's a dream come true for me because when I was young, my parents let me stay up past my bedtime to watch this. That was one of the few nights per year I actually got to stay up past my bedtime, just watch incredible feats that you don't see in a regular baseball game."
And now Dodger Stadium will be his stage next Monday, as he takes a break from a regular season that has New York fans thinking about a postseason run. The Mets enter play on Monday with a 53-33 record and a first-place standing in the National League East. Alonso leads the team with 23 home runs to go along with a .273 batting average and 70 RBIs.
Last year -- with New York bench coach Dave Jauss pitching to him -- Alonso wowed the crowd at Coors Field with a final-round total of 23, in joining Ken Griffey Jr. (1998-99) and Yoenis Cespedes (2013-14) in winning consecutive titles.
"This is just surreal," Alonso said at the time. "It's just truly a blessing."
Alonso confirmed Monday that Jauss will again be his pitcher next week.
"Just need to give him about two pots of coffee for before and a case of Bud Light for after, and he said he's good to go," Alonso said.
The Associated Press contributed to this report.