The promo began innocently enough: "Register for the 2019 US Open Fan Access Pass for a chance to win the Ultimate US Open Experience. The grand prize includes tickets to the 2019 Men’s semifinals, photo on court, restaurant passes, and a prize pack of US Open merchandise."
Then came the gut punch. "And if you don’t win the grand prize, don’t worry there’s more! You will also have the chance to win 2019 Women’s semifinals tickets and a photo on court."
Hmmm. So essentially: if you miss the men, never fear: you can console yourself by watching the women play instead!
The United States Tennis Association (USTA), which runs the US Open, promptly issued an apology on Wednesday night: "While describing the prizes in the Ultimate US Open Experience, the language used inadvertently compared the men's and women's semi-finals unfavourably.
"The grand prize was a reference to a total prize package, including restaurant passes and US Open merchandise, in addition to men's semi-finals tickets and photos on court.”
Silly us I suppose for overlooking the restaurant passes and US Open merchandise. Anyway, by this stage, Judy Murray and Martina Navratilova were among those to have expressed their frustration, with the latter tweeting: "Not a surprise here, but disappointment? That would be a yes."
It is worth pointing out though these issues are hardly unique to the USTA. In fact the USTA has often been at the vanguard of change for equality, becoming the first of the grand slams to introduce equal prize money for men and women in 1973 - a full 34 years before Wimbledon followed suit.
But Wednesday's clanger serves to remind us that even a sport as supposedly progressive - certainly relative to other sports - as tennis still has a long way to go to reach true equality.
Let's start with the eternally thorny issue of prize money, which Wimbledon supposedly resolved in 2007 by awarding the same amounts to men and women. The reality though was that by finally increasing the qualifying size from 96 to 128 this year - in line with the men's event - the 2019 tournament was actually the first where men and women were paid the same total amount.
It also remains the case that women are paid less than men at many joint events. This week for instance, the Western & Southern Open in Cincinnati has a men's singles prize pot of $5 million (£4.14m), compared to $2.8m (£2.2m) for the women.
Then there are the numerous examples of female players suffering at the hands of the schedulers at the biggest events. The worst example came at this year's French Open, when both women's semi-finals were shunted away from the equivalent of Centre Court. Johanna Konta and Marketa Vondrousova were consequently forced to play their semi-final on Roland Garros's third-biggest court.
In response, the Women's Tennis Association (WTA) CEO Steve Simon lambasted the French Open for its "unfair and inappropriate" scheduling.
The WTA itself though has not been immune from horribly misjudging the public mood. During Wimbledon two years ago, the organisation's poll asking for the best dressed player at the tournament was described as putting women’s tennis back "by a century".
Returning to tennis's latest public relations howler, at least the US Open's unforced error might prompt the sport to take a moment of reflection. It should do more than that though, and seek to challenge the institutions that exist simply because they always have. Take the scheduling of grand-slam finals, where every year and at every event it is the men, rather than the women, who are top of the bill with the Sunday finish.
Instead of always casting the women in the role of Saturday warm-up act, why not rotate it from year to year? Look at this year's Australian Open for instance, where Naomi Osaka and Petra Kvitova's thriller was almost half an hour longer than Novak Djokovic's evisceration of Rafael Nadal, and immeasurably more exciting. Or last year's US Open final between Serena Williams and Osaka, which continues to resonate far beyond tennis. By contrast, I expect most non-tennis nerds can't even remember who contested last year's men's final.
By taking these sort of steps, mistakes like the USTA's will become both less frequent and less damaging.