Organizers of the Indianapolis Tennis Championships are planning to sell the sanctioning rights for the ATP event, meaning the city may be without a professional tournament for the first time in more than 80 years.

Tournament director Kevin Martin said Monday that the event's nonprofit group faced serious economic challenges and had explored all options to stay in Indianapolis. He wouldn't say where the tournament might move, but said a sale was expected by the end of December.

The summer tournament has been part of the U.S. Open Series. Its attendance reached nearly 100,000 fans when it drew stars such as John McEnroe and Pete Sampras.

RCA ended its sponsorship deal after the 2006 event and attendance dropped to about 41,000 this year as fewer big names played.

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