CHICAGO – Wrigley Field’s pristine brick wall behind home plate is a throwback – a reminder that the Cubs’ home park is the last holdout of professional stadiums awash in logos and billboards.

But that could change next year.

If they can get approval from the city’s Landmarks Commission – and that might be a big “if” these days – Cubs executives will install a rotating 10-foot-by-3-foot advertising sign just to the right of home plate.

The move is a giant step for the Cubs. It is likely to draw complaints from nostalgia buffs who worship Wrigley’s sun-splashed, ivy-covered outfield walls, as well as the familiar bricks behind home plate.

The brick wall “is one of the great icons of Wrigley Field,” said John McDonough, the Cubs’ vice president of marketing and broadcasting. “But for us, it is important to create a new revenue stream.”

The reason: Player salary increases continue to outpace revenue growth from the turnstiles and the TV networks. In addition, the networks are beginning to balk at paying higher broadcast fees in pro sports.

Beyond the fans, Cubs executives also have to worry about a City Hall backlash. The Cubs, like the Chicago Tribune, are owned by Tribune Co. And Tribune Co. already is in a heated war of words with City Hall over everything from falling concrete at Wrigley to the newspaper’s coverage of Mayor Richard M. Daley.

Now the big question is whether the Cubs will run into foul territory with this new plan. Since Wrigley has landmark status, it’s likely that the Cubs will need approval from the city’s Landmarks Commission. The Cubs intend to apply for building permits.

A major new source of cash hangs in the balance.

Signs behind home plate are some of the biggest revenue generators at baseball stadiums. With estimates of anywhere from $3 million to $5 million a year on average, rotating advertising behind home plate is equal to, or even better than, the annual revenue received for naming rights to the stadium.

For example, when the White Sox secured their 23-year, $68 million naming rights deal with U.S. Cellular last year, that guaranteed roughly $3 million a year.

For the Cubs, a sign behind home plate could be a home run.

The Cubs are one of Major League Baseball’s biggest TV draws, reaching millions of homes nationwide through Tribune Co.’s WGN-Ch. 9 superstation. As a result, the team is likely to demand more of an advertising premium than clubs in other markets.

Neither McDonough, nor Jay Blunk, the team’s director of advertising, has started to solicit advertisers.

Some marketing experts question the value of rotating signs behind home plate for advertisers.

“I think it can be overstated,” said Jim Andrews, editor of the IEG Sponsorship Report, which tracks and places values on sponsorships. “The question you have to ask (is), “Does someone seeing that make a connection with that sign and support of the Cubs?’ It’s not as valuable as a promotion like a bank giving you tickets for opening an account. In the end, it’s still just a sign.”

But advertisers are eager to reach an even broader audience, and that’s on TV. As a result, signs already have been quietly creeping into Wrigley.

In 2002, Cubs executives signed a deal with Sears, Roebuck and Co. to wallpaper the dugouts with the Sears logo. This season, the team added lighted signage under the scoreboard and along both the right- and left-field upper decks that included advertisers such as McDonald’s Corp. and Culver’s.

But the move to add a sign behind the plate would be the first time the club has allowed a permanent sign to creep into a spot considered by many to be sacred.

Criticism would be blunted because the Cubs are not the first team to sell its backstop.

“The fact they’re one of the last teams to do it will mute it,” said Marc Ganis, president of sports consulting company SportsCorp. Ltd. But he quickly added: “Wrigley is a shrine to many people, and any changes – especially more modern ones – will always have some people critical about it.”