The Chicago Cubs have considered opening a sportsbook at Wrigley Field and at locations just outside of the Friendly Confines, multiple sources familiar with the team's thinking told ESPN.

Betting windows, automated kiosks and even a full-blown sportsbook venue inside the stadium are among the options that have been considered by the Cubs and other Chicago professional franchises, as Illinois prepares to put its new sports gambling law into effect.

The Cubs declined to comment, and there are no official plans, only preliminary discussions at this point. Who would run the sportsbook and which parties would receive a cut of the action is unknown.

"Pen hasn't hit paper yet," a source familiar with the team's thinking told ESPN.

MLB currently prohibits sportsbooks, including betting kiosks or windows, inside a club's stadium. The NBA has similar rules in place prohibiting retail sportsbooks from offering in-person betting inside arenas. The leagues are reviewing the Illinois legislation.

"We will work with our clubs to explore the opportunities presented by the rapidly evolving sports betting landscape in a socially responsible manner," a spokesperson for MLB told ESPN in a statement.

On June 2, the Illinois legislature passed SB 690, authorizing regulated sports betting. The bill is awaiting the signature of Gov. J.B. Pritzker, who was supportive of the legislation that will bring a casino to Chicago and potentially sportsbooks to the state's professional stadiums.

Under the legislation, which was supported by MLB, the NBA and multiple team owners, sports facilities with seating capacity greater than 17,000 could apply for a license to offer sports betting inside or within a five-block radius of the venues. Soldier Field, home of the Bears; United Center, where the Bulls and Blackhawks play; and Guaranteed Rate Park, the White Sox's stadium, are among the venues that can apply for a masters sports wagering license, which costs $10 million.

Securing rights for stadiums to operate sportsbooks has also been pushed by MLB and the NBA in New York and Washington, D.C. Ted Leonsis, the owner of the Washington Capitals and Washington Wizards, has talked about opening a sportsbook at Capital One Arena in Washington, D.C.

Soldier Field, United Center and Guaranteed Rate Field are said to also be examining any sports betting opportunities afforded by the legislation. The Bears, Bulls and White Sox each declined comment. The NFL also did not respond to multiple requests for comment.

"We are following the discussions about sports betting at sports venues," said Denny Hartwig, director of communications for the Chicago Speedway, one of the sports venues that could apply for a betting license. "We have not made any decisions and have no definitive plans for sports betting at the speedway."

Sportsbooks at stadiums were discussed at MLB's winter meetings in December in Las Vegas, seven months after the U.S. Supreme Court struck down the Professional and Amateur Sports Protection Act of 1992, the federal statute that had restricted state-sponsored sports betting to primarily Nevada.

Though only in the preliminary-discussion stage, the Cubs have considered opening a sportsbook at Wrigley Field or at locations just outside of the Friendly Confines, multiple sources have told ESPN's David Purdum. Patrick Gorski-USA TODAY Sports

Since the ruling, legal, full-scale sportsbooks have begun operating in Delaware, Mississippi, New Jersey, New Mexico, Pennsylvania, Rhode Island and West Virginia. Upstate New York casinos are preparing to offer in-person sports betting in the coming months, and the New York state legislature is considering a bill that would allow mobile sports betting and sportsbooks at stadiums. The bill faces tough odds, with the legislative session in New York slated to end this week.

Indiana, Iowa, Montana and Tennessee have passed sports betting legislation this year, and bills in Illinois and New Hampshire are awaiting governors' signatures.

As sports betting has expanded around the U.S., professional leagues and franchises have struck partnerships with bookmakers and casinos. In late November, MLB announced MGM Resorts as an official betting partner. No team has opened a sportsbook inside a stadium, though. Sports venues in the United Kingdom, including Wembley Stadium, have sports betting windows and kiosks.

In Illinois, the Cubs appear to be the furthest along in getting involved in sports betting, although representatives of the White Sox, including Hall of Famer Frank Thomas, also were involved in lobbying for the bill.

The NBA and MLB's lobbying requests in Illinois appeared in early versions of the legislation and included a royalty fee paid by bookmakers to sports governing bodies based on the amount wagered, data rights and the sports venue language. There was strong opposition to the royalty and data rights, but there wasn't immediate or forceful pushback about the sports venues, said Illinois state Rep. Mike Zalewski, one of the bill's initial sponsors.

The royalty did not make it into the final bill, but sportsbook operators will be required to use official league data to grade some wagers, and the sports venues do have the option to offer betting.

"It didn't surprise me that the [stadiums] concept was raised," Zalewski told ESPN in a social media message. "My sense was the leagues and the teams, and the Cubs specifically, were looking for unorthodox ways to capitalize the ballparks in an age where fans are glued to their phones."

In February, Cubs owner Tom Ricketts invested in sports betting media outlet The Action Network, and in March, Cubs president of business operations Crane Kenney said on an appearance on Chicago radio station 670 The Score that the team is considering a secondary broadcast infused with sports betting analysis.

"Look, Wrigley Field draws people year round," Vic Salerno, founder of sportsbook operator US Bookmaking and a member of UNLV's Gaming Hall of Fame, told ESPN. "It's going to be a great location for them."

Asked if he thought it would be feasible for the Cubs to open a sportsbook by next baseball season, Salerno said, "Oh, yeah. For sure."