CHICAGO -- Len Kasper had to request permission from the Cubs to pursue the opening on the opposite side of town in the White Sox radio booth. It was an opportunity for Kasper to follow in the footsteps of his hero, idol and eventual friend, the late Ernie Harwell.

Kasper grew up listening to Harwell's calls of the Detroit Tigers and dreamed of one day describing baseball over the radio. As much as the Cubs wanted and tried to keep Kasper in the Marquee Sports Network television booth, the team allowed Kasper to realize his lifelong goal.

"We had to allow for this to happen," said Mike McCarthy, the general manager of Marquee Sports Network. "We happily did, because you don't ever want your legacy to be you stood in the way of somebody and their dream. And this is by no means anything other than him chasing his dream. While we have work in front of us, we're quite happy for him."

On Friday morning, Kasper was officially named the new radio voice of the White Sox for ESPN 1000 after 16 seasons as part of the Cubs' TV team. When the news broke overnight, the reaction across the fan bases on both sides of town felt similar to a blockbuster offseason player acquisition.

Now, the Cubs are tasked with replacing a beloved broadcaster, who in 2020 equaled legendary play-by-play man Harry Caray in years spent on the North Side. Kasper also joins Caray, Jack Brickhouse and Steve Stone on the list of broadcasters who have worked for both the White Sox and Cubs.

"We'll be very careful," Crane Kenney, the Cubs' president of business operations, said of the team's search for Kasper's replacement. " It needs to be someone who fits with our culture. And I mean the Cubs culture, not ownership culture, because the Cubs culture is very special and, as you know, something we cherish."

In a Zoom call with White Sox and Cubs reporters, Kasper emphasized and reiterated multiple times that his decision was purely about making a move to radio. He enjoys the creative freedom that radio allows and has always wanted to call October baseball in addition to the regular season.

And Kasper, whose first full-time play-by-play job was with the Marlins, became emotional when mentioning Harwell.

"Ernie was the hero who became a mentor and a good friend," Kasper said. "When I got the Marlins job, I got a handwritten letter from Ernie. And when I got the Cubs job, I got a phone call from Ernie. You just don't know how much that means to somebody like me. So, I'm thinking about you, too, today, Ernie."

Kasper, who was still under contract with the Cubs and Marquee Sports Network, wanted it to be clear that his departure was in no way related to any negative feelings about the team or its network operations.

He noted that Marquee's leadership presented him with a counter offer this week that blew him away, but it did not change his desire to move to a radio booth. Kasper also said that he would not have made this move if the opportunity involved moving out of Chicago.

"This is my decision," Kasper said. "The Cubs and Marquee did everything they could to keep me with the club. I can't thank them enough for how they handled it. At the end of the day, I'm trying to live out my dream."

There were reports late Thursday that Chris Myers, a broadcaster with more than 30 years of experience who is a part of the Marquee team, was in line to replace Kasper, alongside analyst Jim Deshaies. McCarthy noted that Marquee is working with Myers on a new talk show, but no decision had been made in relation to Kasper's former post.

Both McCarthy and Kenney noted that they have received a wave of messages from parties interested in the sudden opening in the Cubs' TV booth. The Cubs plan on taking their time with examining all of their options -- names considered internally, along with those reaching out to the team -- before making their new hire.

"We're going to look at every possibility," McCarthy said. "The good news is, with a job like this, one of the real pearl positions in sports broadcasting, we're going to end up talking to quite a few people. We'll try to map it out in the best way possible. I don't think we're ruling anything out at this stage."