NEW YORK ( TheStreet) -- Move over Art Modell, there's a new villain in Ohio. Basketball superstar LeBron James announced his decision to leave Cleveland Cavaliers and join fellow All-Stars Dwayne Wade and Chris Bosh with the Miami Heat Thursday night, instantly making himself persona non grata in his native Buckeye State. For stock-market watchers, the ticker in the crosshairs on Friday will be Madison Square Garden Inc. ( MSG), the company that owns its namesake "World's Most Famous Arena" and the NBA franchise that plays there, the New York Knicks. Shares of Madison Square Garden surged earlier this week, making a plus 5% move on Wednesday, before pulling back in Thursday's session as reports began to surface that James was leaning towards signing with the Heat. While it's difficult to quantify exactly how the signing of James would have impacted Madison Square Garden's bottom line, making the Knicks, which have suffered through nine straight losing seasons, relevant again would have been a major shot in the arm. For example, UBS analyst Thomas E. Cubeta estimated a James's signing could add $5 a share in value to Madison Square Garden's stock, according to a Wall Street Journal report on Thursday, where he factored in the impact of higher ticket sales and a return to the playoffs. The Knicks had spent years in preparation for making a run at James, clearing salary cap room in hopes of signed at least two free agents to maximum contracts in order to entice the winner of multiple MVP awards. The team has already signed power forward Amar'e Stoudemire this off-season, a five-time All-Star with the Phoenix Suns, and was hoping to pair him up with James and become a legitimate contender for the first time since the late nineties. The stock finished on Thursday at $20.38, down 5.5% for the session. MSG shares were spun off from Cablevision Systems ( CVC) in February.
The other ticker that could move on the news is Walt Disney Co. ( DIS), which owns ESPN, the cable channel that provided exclusive live coverage of James's announcement, surely a ratings bonanza. Disney shares closed Thursday at $33.34, up 20 cents, and the stock has risen 3.4% since the start of the year. -- Written by Michael Baron in New York.