The Prairie Avenue apartment building -- described by the city as a slum nuisance -- sits a short drive from where Antoine Walker once dominated basketball games, a prodigy at Mount Carmel High School on his way to escaping South Side poverty to become a fabulously wealthy NBA star.

At one point, bricks fell off the building's facade, a hazard that went unfixed for months, city records show. Before that, a broken sewer pipe filled the basement with feces, toilet paper and other debris, creating an odor that forced families to move their children out.

The angry tenants don't know Walker, 33, who reportedly earned $110 million during a 13-year pro career that included winning an NBA championship ring. But the 6-foot-9 former all-star -- known for a partying lifestyle that stretches from the golf course to the velvet-rope club -- plays a big role in their lives.

His company owns the building.

Amid a pile of financial troubles and legal actions capped off earlier this year with his arrest in Nevada for nearly $1 million in bad gambling debts, Walker is being pursued by city officials, bank attorneys and tenants' lawyers for housing problems that have resulted in what the city says are public hazards.

Real estate investment companies that list Walker as an investor or principal -- Walker Ventures LLC and AW Realty LLC -- are the target of more than a dozen lawsuits alleging poor management of numerous properties, unpaid debts and damages caused by shoddy repair work. In one case last month, the city won $950,000 in court-ordered fines against Walker Ventures.

Speaking to the Tribune Friday by telephone, Walker appeared contrite about the problems, blaming them on the bad economy, "a lot of financial mistakes throughout my career," and putting trust in other people. "I would like to humbly apologize to everyone who has been affected by the failings of my company," Walker said. "It was never intended to present [tenants with] unacceptable living conditions."

In an era of celebrity scandal and richly rewarded fame, it's not unheard of for a multimillionaire athlete to suddenly turn up with financial problems. But as Walker carved a path of luxurious living from Chicago to Miami to Las Vegas, running up millions of dollars in debts to banks, casinos and at least one agent, the company bearing his name was leaving scars on the poor, urban landscape of his youth.

On Cornell Avenue, a 13-unit building developed a mold problem so bad that a 7-month-old boy repeatedly woke up coughing, a tenant lawsuit says. The toxic fumes and a lack of heat drove all the tenants to abandon the building, which the city declared "a hulking public nuisance" before Walker Ventures eventually lost it in a bank foreclosure.

On Minerva Avenue, another Walker Ventures building suffers from spotty electricity and a mouse and roach infestation that resulted in its failing several inspections tied to federal rent subsidies, government records show. Shoddy conditions and a problem with squatters drove most tenants away, and this month a team of city inspectors and police found several code violations, city officials said.

In Country Club Hills, raw sewage leaked from bad pipes inside a condominium owned by Walker's AW Realty and managed by his mother, Diane Walker, according to a Cook County lawsuit that described how the leak destroyed the unit below.

Many of the tenants were surprised to learn that their problems traced back to a former NBA star.

"This is your property and you're supposed to be somebody?" demanded Kywanna Leftridge, 29, who lost most of her belongings and had to move temporarily into a homeless shelter with her son, 13, after her apartment in the Prairie Avenue building flooded. "It was horrible."

Steven McKenzie, an assistant city corporation counsel, said that a number of foreclosed and now-abandoned properties have grown into neighborhood nuisances. One of the examples he cited was the Cornell Avenue building, which leaked natural gas in the vestibule as squatters were smoking upstairs, a fire hazard documented in court records.

Known as affable and media friendly, Walker has been elusive when it comes to many of the property accusations. The tenants haven't seen him, and lawyers have been unable to find him to serve papers. McKenzie did extensive research, pulling records available only to law enforcement, to make sure the former NBA player was the same Antoine Walker behind the real estate company.

The former star for the Boston Celtics, Dallas Mavericks and Miami Heat -- who has not signed with another team this year -- talked to the Tribune Friday from Chicago in a telephone interview arranged by his publicist in New York. Before that, he had not returned repeated messages left by the Tribune with his attorneys, family and friends.

In Tinley Park, Walker's mother, Diane, struck a tired air of defiance this month at the door of the $2.5 million mansion the ballplayer bought her. In the brick driveway, engraved with a large "W," sat four luxury cars.

Diane Walker defended her son, noting how he has counseled troubled teens and helped others pay for college through his charitable Eight Foundation. "Talk about the goodness of his heart and what he's done," she said.

Of the two real estate companies tied to the athlete, Walker Ventures has been most aggressive during the past several years about acquiring apartment buildings -- mostly on Chicago's South Side. The company was launched out of Coral Gables, Fla., in 2006, the same year Walker helped the Miami Heat win the NBA championship, according to Florida state records.

As a limited liability company, it lists three principal "members," or owners, including Walker. In addition to using Walker's name, the company features his address and signature on its registration paperwork.