Diana Ross had at least one surprise up her sequined sleeve at her Sunday night concert at The Rady Shell at Jacobs Park — and it was as welcome as it was unexpected.

No, it wasn’t the fact this seemingly ageless star — still getting her groove on at 79 — only left the stage twice to change from one eye-popping ensemble into another.

“You guys don’t get to get the last costume change!” Ross told the audience, after claiming not to know The Shell has a 10 p.m. curfew (a fact clearly stipulated in her performance contract).

It also wasn’t surprising that her 10-piece band was featured at length on several songs, the better to let Ross catch her breath offstage as she exchanged one brightly colored gown for another.

But what was surprising — and inspiring — is that a highlight during her hits-packed “The Music Legacy Tour 2023” concert here came with a relatively new selection few in the audience had heard before.

That song, the brassy, dance-happy “Tomorrow,” is a standout from 2021’s commercially moribund “Thank You,” Ross’ first new album since 2006’s “I Love You.”

She delivered “Tomorrow” — which came 70 minutes into her 90-minute performance — with infectious verve and energy. Ross sounded thoroughly engaged with the song, whose release came seven decades after she made her recording debut with “I Want a Guy.” (Released in 1961, “Guy” was her first single with the pioneering Motown vocal group The Supremes.)

Diana Ross performed Sunday night to a near-capacity crowd of 4,400 at The Rady Shell at Jacobs Park.

(George Varga / The San Diego Union-Tribune)

Audience cheered heartily

Sunday’s near-capacity audience of 4,400 had a muted response when the legendary diva announced she was about to do a number from her latest album. But they cheered heartily when it concluded.

The enthusiastic reaction was a testament to the propulsive “Tomorrow’s” melodic appeal, its upbeat lyrics and to how thoroughly the nearly 80-year-old Ross threw herself into the forward-looking song.

“Some of you old-timers may not know that I have a new album,” she lamented. “You can’t hear the songs on the radio; you gotta go to Spotify or Apple. It’s different these days.”

“Tomorrow” was, alas, the only piece she included from “Thank You,” which is the 25th studio album of her career as a solo artist. Her concert at the Shell — as denoted by its “Music Legacy Tour” moniker — was crafted to celebrate the breadth and depth of her improbably long career.

That Ross only partially succeeded reflected just how formidable her repertoire remains. Or, as she succinctly noted: “I have too many songs, that’s for sure.”

Her surfeit of memorable material necessitated some trade-offs. So, while “Ain’t No Mountain High Enough,” “It’s My House” and The Bee Gees-penned “Chain Reaction” were included in her set list Sunday, “You Keep Me Hanging On,” “Reflections” and her 1977 funk gem “Baby It’s Me” — by the great San Diego singer-songwriter Don Dunn — were among the songs that didn’t make the cut.

Ross took to the stage following a six-minute film that traced her rise from a Detroit housing project to international stardom.

The multi-generational audience cheered nearly as loudly for some bits in the film as for the concert that followed. And if Ross repeated on stage at least one line from the film — “I’m still here! I’m not going anywhere!” — well, it was a line worth repeating.

In the unlikely event, any concertgoers were daydreaming or somehow forgot whose legacy was being saluted, the large video screen at the rear of the stage offered nonstop reminders throughout the performance. Vintage photos and film clips showed Ross with The Supremes, throughout much of her subsequent solo career and with various collaborators, including Marvin Gaye and Michael Jackson.

She opened the show with her celebratory 1980 hit, “I’m Coming Out,” which was written by Nile Rodgers and Bernard Edwards of Chic. Her rendition clocked in at two minutes, less than half the length of her original album version.

Ross also zipped through five crowd-pleasing classics by The Supremes, starting with “Baby Love” and “Stop! In the Name of Love,” that averaged 2-1/2 minutes each. The fifth, “Love Child,” was extended to 5 minutes, but she was offstage for three of them for her first costume change.

Returning in a red gown and red ruffled cape, Ross delivered winning, back-to-back versions of two of her disco hits: 1979’s “The Boss” and 1980’s “Upside Down.” Both benefited from the sleek, note-perfect performances of her well-drilled band.

Ross played the audience as if it was a musical instrument at her fingertips, leading them in mass sing-alongs and arm waves. She won cheers when she chided security guards at the front of the stage who were trying to clear the aisles of dancing fans. It was a thankless and, ultimately, impossible task.

Diana Ross, left, is shown with Mary Wilson, center, and Florence Ballard, right, as their Motown vocal group, The Supremes, rehearse for their performance on the TV show Hullabaloo on May 11, 1965 in New York City.

(Donaldson Collection / Getty Images)

Girlish lilt

Ross’ voice has always been thin and wispy. It has grown more so with age, so she wisely had her four backing singers do much of the heavy lifting.

But her voice has retained much of its girlish lilt, while her personality and charisma enabled her to largely hold her own whether she was breathlessly crooning through the unabashedly sentimental ballad “Missing You” or romping through “Love Hangover.” And hearing her voice crack during her concert-concluding version of Gloria Gaynor’s pulsating 1978 ode to resiliency, “I Will Survive,” provided added pathos to the lyrics.

Ross didn’t dance up a storm from start to finish — she is a septuagenarian, after all.

But she was on her feet for the duration of her nearly two-dozen selections, offtage costume changes notwithstanding. And she knew exactly when to strut or add a well-timed shimmy-and-shake for maximum impact. For good measure, at one point during “Upside Down” she playfully patted her derriere.

“Now look,” Ross told the audience. “If I can move my body like this when I’m 47 — you know, I’m kidding, I’m 79 this year — (you can) move that body!”