Sports Authority, the Colorado-based sporting goods chain, apparently failed to find an 11th-hour buyer for the bulk of its operations and is proceeding to close all of its more than 450 stores, about a dozen of those in the Sacramento region.

The company made it intentions known in a new filing in U.S. Bankruptcy Court in Delaware. Liquidation sales could begin at Sports Authority stores as soon as Wednesday and conclude at the end of August, although court documents give liquidators some leeway on the closing dates.

On Thursday, spokeswoman Monique Sidhom sent this email reply to Sacramento Bee questions: “Sports Authority is not commenting beyond the court filing.”

Sports Authority, struggling amid intense competition in the sporting goods market and increasing numbers of shoppers shifting to making major purchases online, filed for Chapter 11 bankruptcy protection in March, announcing plans to close 140 of its 463 stores and to reorganize its remaining business after reaching agreement with its creditors.

However, lawyers for Sports Authority notified the federal bankruptcy court in Delaware in late April that a reorganization plan had failed to get approval from creditors and lenders.

That prompted the decision to pursue the selling of assets, which some retail analysts quickly interpreted as the first move by Sports Authority to close all its stores.

The retailer quickly countered, calling reports that all stores would be closing premature.

At the beginning of May, Sports Authority issued a statement that said it was “pursuing a sale of some or all of the business” and that there is interest from some potential buyers.

It is still possible that some Sports Authority stores could be snapped up by competitors.

The Denver Post reported on Thursday that Pennsylvania-based Dick’s Sporting Goods is interested in a “very small number” of Sports Authority stores.

Sports Authority’s regional presence includes two stores in Sacramento and individual stores in Citrus Heights, Folsom, Elk Grove, Roseville, Modesto, Fairfield and Vacaville.

Sports Authority, which had nearly 15,000 part- and full-time employees at the time of its bankruptcy filing in March, reportedly is saddled with more than $1 billion in debt.

In 2006, Sports Authority agreed to be purchased in a leveraged buyout led by the Los Angeles-based private equity investment firm Leonard Green & Partners. That transaction was valued at $1.4 billion.

Among other questions to be answered in the coming months: What becomes of the naming rights to Sports Authority Field at Mile High, home stadium of the Denver Broncos, the reigning Super Bowl champions of the National Football League?