Soto, who won the National League Rookie of the Year in 2008, is one of three talented catchers on the Puerto Rican team, joining Ivan Rodriguez and Yadier Molina. Cubs special assistant Ivan DeJesus also will participate as a coach for Puerto Rico.
Lilly is on Team USA, while Perkins will pitch for Canada. Cubs outfielder Kosuke Fukudome, who has been training in Japan, will play for the defending champion Japanese team for the second time.
Soto was excited to take part in the event.
"It'll be a good experience to be out there with the guys, and put on a Puerto Rican uniform," he said Tuesday.
The plan is for Soto to be the designated hitter in Puerto Rico's first game against Panama, then catch the third game, which San Francisco's Jonathan Sanchez was scheduled to start.
"It won't set me back at all," Soto said of playing in the World Baseball Classic. "I'll still be working and we'll be playing in a playoff atmosphere down there. I don't think it'll hurt me at all. They're not going to kill me and make me play every single day. I'll rotate."
Team USA will train in Clearwater, Fla., and open play against Canada in Toronto. Lilly got his first feel for the event on Monday when he posed wearing a U.S. jersey for photo day.
"I never had a chance to play for my country or represent my country in the service or baseball or any other way," Lilly said. "As a child, that's something I thought I would do. My grandfather and my father and my uncles all served in the Navy. That's something I thought I would have a chance to do. This is the next closest thing."
He'll be the first player named after a president to participate. Theodore Roosevelt Lilly was so named because his great grandfather worked for President Roosevelt's Rough Riders.
"That's a story that's passed down from my dad," Lilly said.
Lilly got a head start this offseason, amped up his workouts and threw off the mound five times. In the past, he had thrown off the mound once and sometimes not at all. Part of the reason was to make sure he was ready for the World Baseball Classic and part of the reason was that he wanted to get off to a better start. Lilly was 1-4 with a 6.46 ERA last April, and he blamed part of that on the fact that he was relying too much on his changeup.
Perkins, 27, pitched in the inaugural World Baseball Classic for Canada. An 18th-round pick in 2000 by Toronto, he has a 29-32 career Minor League record and 3.85 ERA.
Fukudome was 4-for-22 with two home runs and six RBIs in eight games in 2006 for Japan, which beat Cuba to win the event. In the Japan team's last exhibition game last weekend, he hit a grand slam against the Toyko Giants.
The Cubs will have two Minor Leaguers also competing in the World Baseball Classic. Alex Maestri will pitch for Team Italy for the second time. Maestri, 23, was 5-3 with a 3.89 ERA in 15 games for Class A Daytona, and pitched in two games for Double-A Tennessee last season. Right-hander Hung-Wen Chen, who pitched at Class A Peoria and Class A Daytona in 2008 for the Cubs, will be on the Chinese Taipei team.
The first round opens March 5 in Tokyo, with Japan facing China. Mexico City, Toronto, and San Juan, Puerto Rico, host the other three first-round brackets, as follows:
Tokyo (March 5-9): Japan, China, Chinese Taipei and Korea
Toronto (March 7-11): USA, Canada, Venezuela and Italy
San Juan, Puerto Rico (March 7-11): Puerto Rico, Dominican Republic, Netherlands, Panama
Mexico City (March 8-12): Mexico, Cuba, South Africa, Australia
The World Baseball Classic will be a double-elimination format in the first two rounds. The winners from Toronto will meet the winners from Puerto Rico in the second round at Miami's Dolphin Stadium, while the winners from Tokyo will meet with the winners from Mexico City in San Diego's PETCO Park.
The semifinals and finals will be played March 21 and March 23 at Dodger Stadium.
Carrie Muskat is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.