Nestled in a park on the border between some of the richest and poorest neighborhoods in Dallas sits an obscure public tennis court. It would hardly be worth mentioning if it hadn’t unexpectedly played host in 1965 to Arthur Ashe in a Davis Cup finals match.

The match was supposed to have been played at the exclusive Dallas Country Club, but there was a small problem. Mr. Ashe, the management said, would be approved to play on the courts, but owing to the fact that he was of the, uh, Negro persuasion, he would not be permitted to access the locker room facilities. Nor would others of his persuasion be permitted on the grounds to watch.

Mr. Ashe, who attended formerly segregated Sumner High School here, opted out of play at the Dallas Country Club so as not to soil its pristine tennis courts with his, uh, persuasion. The solution was to move the Davis Cup match to the Samuell Grand public tennis courts, where organizers quickly scrounged enough money to erect grandstands and concession facilities to accommodate crowds estimated at 3,500 per day for the three-day event.

This being less than two years after Dallas had generously hosted the assassination of President John F. Kennedy, the city did everything it could to downplay the awful genesis of the Samuell Grand tennis courts’ claim to fame. (Just down the street from Samuell Grand are the grounds of the State Fair of Texas, which once officially celebrated Ku Klux Klan Day.)

I knew the Arthur Ashe story because those were my neighborhood courts. Which meant I got to play on the same grandstand-ringed court where one of the all-time greats of tennis once played. The only reason this story comes to mind is that, last weekend, I went to see the film “The Green Book,” starring Mahershala Ali and Viggo Mortensen. It tells the true story of Don Shirley, an African-American classical and jazz pianist, as he attempted in 1962 to tour the Deep South and, perhaps, raise the consciousness of his white affluent audiences.

The film’s title comes from “The Negro Motorist Green Book: An International Travel Guide,” a listing of hotels, motels, restaurants and other public places where blacks could feel safe and welcome. The Dallas Country Club most definitely was not among its listings.

Shirley was under no illusions about the dangers and humiliations he would face on the tour. Years earlier, singer Nat King Cole would attempt a similar tour, only to be beaten bloody by Klan members during a performance in Birmingham, Ala.

To help ensure that Shirley would reach his concert venues on time and unscathed, he and his record company hired Tony “Lip” Vallelonga, a beefy Italian-American nightclub bouncer from the Bronx renowned for knocking heads together in a neighborhood where Mafia career-advancement opportunities often required such talents.

In the film, Vallelonga has his own racist proclivities but undergoes what you might call a cultural transformation during his weeks on the road with Shirley, who held doctorate degrees in music, psychology and liturgical arts. Vallelonga’s repeated exposure to the cruelties and humiliations inflicted on blacks in the South leads him to put everything on the line in Shirley’s defense.

They arrive at one country club-style concert venue, where Shirley is greeted as an honored guest. He is, after all, a piano virtuoso whose culture, class and education are depicted in sharp contrast to the unfiltered, slob-like mannerisms of Vallelonga. When Shirley is shown his dressing room, it is clear that the management has done little more than clear out a storage closet for him. When Shirley attempts to join his two trio members and Vallelonga in the dining room before their performance, the maitre’d asks if he would perhaps be more comfortable dining at the restaurant down the road. For folks of his persuasion.

At another performance venue, Shirley again gets the honored-guest reception, but when he heads to the men’s room, the manager stops him, then tries to usher him outside toward a wooden outhouse. There are other egregious examples of mistreatment by police and bar patrons.

I won’t give away much more of the film. Shirley’s family says the film is inaccurate to the point of containing outright fabrications. But no matter how much dramatization you attribute to Hollywood hype, the overt racism was as real as it got, and it didn’t stop at the Mason-Dixon Line. Nor did it stop in 1962.

Which is why I tell the unhyped story of Arthur Ashe and the Dallas Country Club. It would be nice to write that those were bygone days and that we as a nation have modernized to a new way of thinking about diversity and inclusion. But our journey is still very much in progress. Thanks to courageous pioneers like Don Shirley and Arthur Ashe, it’s a good deal shorter.