How much for Wrigley Field's naming rights?

How much money are the Cubs leaving on the table by not renaming Wrigley Field?

That question was posed following today's announcement from the Chicago White Sox and U.S. Cellular that, while U.S. Cellular is selling its Chicago, St. Louis and central Illinois markets for a reported $480 million to Sprint/Nextel, "U.S. Cellular Field" will remain unchanged.

The White Sox signed the original deal with U.S. Cellular in 2003 for $68 million over 20 yearas, with the agreement paying the White Sox $3.4 million per season for the stadium's name, as well as an agreement to purchase significant advertising with the White Sox each season as a corporate sponsor?

So what about the stadium on the North Side?

Industry sources I spoke with all seem to believe that if a deal were to be completed to change the name it could generate $15-20 million a year, but they all cautioned that it comes with significant risk for the company that puts up the tremendous amount of money that it would take to reach an agreement.

"I can see the Cubs selling a secondary naming rights opportunity or perhaps naming each individual gate entrance to the stadium like the Yankees did. Something like Wrigley Field at 'XYZ park' would work, but the Cubs attract fans who want the Wrigley Field experience and if you change the name and you put in a Jumbotron, etc., how much does it change the experience of going to Wrigley Field which is one of the last true old time experiences in sports?" Jon Greenberg said.

One highly placed source who is a former owner who spoke to me on a condition of anonymity estimated that the Cubs are leaving an incredible amount of money on the table by staying at Wrigley Field and not selling naming rights to the stadium.

"There is no doubt in my mind that if the Cubs were willing to leave Wrigley Field and build a state-of-the-art stadium with all of the amenities that fans have come to expect these days, they would be able to make a deal in the range of $20-25 million per year. However, if I was running a major corporation and I was asked to buy the naming rights to a renovated Wrigley, I would not touch that deal because of the potential for negative backlash from the Cubs' huge fan base who have known that ballpark as Wrigley Field Field for nearly 100 years," he said.