Lady Gaga in Versace for her Super Bowl halftime performance on Sunday. Credit Chang W. Lee/The New York Times

Last year, Lady Gaga belted out the national anthem at Super Bowl 50 in a red Lurex pantsuit by Gucci, but this time around, for her starring performance at halftime on Sunday — beginning with her plunge off the roof of NRG Stadium in Houston like some kind of giant sci-fi angel, dazzling the audience with both her Swarovski-covered shine and her performance — she turned to her old friend Donatella Versace.

Why? Not just because Ms. Versace knows a statement outfit when she makes one, or because she’s a designer who understands how to dress a power woman, or because she has had some experience with Super Bowl style having outfitted Bruno Mars for his duet with Beyoncé at Super Bowl 50. But it was also because the choice helped to support a subtler, arguably more powerful, message.

Versace is “ family to us; we’ve worked together for so many years,” said Brandon Maxwell, Lady Gaga’s longtime stylist.

Indeed, the two are so close, Lady Gaga wrote a song about Ms. Versace (“Donatella,” on “Artpop”) and starred in a 2013 Versace ad campaign as the designer’s doppleganger. Rumor was she had been cast to play Donatella in the coming “American Crime Story” mini-series on the murder of her brother Gianni Versace, although that has now been denied.

In a show of mutual support, Ms. Versace flew to Houston and watched from the stands. She even Instagrammed a photograph of herself and Lady Gaga backstage getting ready. (As an aside, the bio on her Instagram reads: “Me, Donatella. I believe in individuality and the freedom to be whoever you want to be” — sound familiar?)

According to Mr. Maxwell, Ms. Versace even “helped zip up” the leotard. Which, in case anyone was wondering, was actually a “custom fully beaded iridescent jumpsuit with sculptural shoulder detail paired with fully embroidered boots, both embellished with Swarovski crystals.” There also were Swarovski crystals all over the “custom gold cropped jacket accented with spiked shoulder pads” and the hot pants-plus-cropped sculptural white jacket with metallic hardware look that Lady Gaga wore at the end.

That’s a lot of sparkle.

Yana Paskova for the New York Times

Ultimately, the outfits with all their crystals were less the point than the relationship behind them. Along with Lady Gaga’s midperformance shout-out to her mom and dad, her highly diverse backup casting and her choice of songs (including “This Land Is Your Land” and “Born This Way”), the Versace connection gave an added dimension to her promise of a show that was about “inclusion.”

The point: Family is what you make of it; the bigger, the more expansive, the better. That’s not explicitly political, but it is pointed. No matter how dressed up in glamour it comes.

To that end, she didn’t limit the looks to Versace, but opened it up to the wider fashion clan. Her dancers all wore Dr. Martens boots, and she sported a black Vera Wang cropped sweater and a silk cutaway miniskirt with an enormous train to the pregame show and photo op.

(Enlarging her purview even more, she appeared earlier in the evening in Tiffany’s first Super Bowl ad wearing a simple black turtleneck and a charm bracelet from its new HardWear line, which was inspired by industrial design and by a unisex bracelet from 1971. That particular expansion may have been less broadly convincing, however, given that just before the commercial was shown, the news broke that Frederic Cumenal, the Tiffany chief executive, was stepping down.)

Still, after the halftime show, and until the Patriots’ astonishing comeback, social media was pretty unanimous in declaring Lady Gaga the winner of the night — although W magazine bestowed that honor on Ms. Versace.

In fact, it may be their collaboration, and the cross-border meeting-of-the-minds it represents, that triumphed.