Gladys Knight & Patti LaBelle Face Off in 'Verzuz' Battle -- See the Best Twitter Reactions

Gladys Knight & Patti LaBelle
Johnny Nunez/WireImage

The icons faced off for a night of incredible music, and got some help from Dionne Warwick.

Gladys Knight and Patti LaBelle's Verzuz battle proved to be a timeless celebration of music. On Sunday, the two icons sat down to belt out their most beloved hits and talk about their legendary careers.

The showdown -- which took place at Philadelphia’s Fillmore Theater -- was part of the Verzuz web series on Apple Music and Instagram, which pits musicians against each other in a friendly musical competition.

However, the historic diva get-together proved to be a wonderful opportunity to hear stories from their past and for the two titans to both shower each other with a lot of love and show what made them music icons in the first place.

The pair made sure to bring their very best, and it showed in the sheer, undeniable strength of their head-to-head set list.

Needless to say, the event was a cause for celebration among music lovers, many of whom took to Twitter to share their appreciation for how impressive, enthusiastic and exuberant Knight and LaBelle have remained through all these years.

The pair sang live along with their records and their flawless vocals earned a lot of love and praise on Twitter.

The two icons also demonstrated the occasional diva flourish, like when LaBelle kicked off her shoes or did her make-up like she owned the entire theater.

While the pair are undeniable legends, that doesn't mean they don't get starstruck and fangirl out themselves. Twitter couldn't get enough with how much respect and appreciation the two shared for Michelle Obama and Oprah Winfrey, who both tuned in to watch the event.

So how do you top off a show that already featured two musical giants? You bring on a third! To finish off the epic Verzuz "battle," Knight and LaBelle were joined by Dionne Warwick, and together they all performed a rendition of "That’s What Friends Are For."

The addition of another member of music royalty just sent fans over the edge.

The star-studded showdown came to an end with an important message, with the icons urging viewers to get out to vote, and make their voices heard.

"We have to vote," Knight shared. "We can make a different by doing that."

ET's Nischelle Turner spoke with the pair about their performances tonight, and they reflected on how nice it was to do something that felt like touring again, after being stuck at home for so long due to the pandemic.

"We felt close to being on the road tonight," LaBelle shared.

The two have long been friends, but this was the first time in a long time that they've been able to reconnect and spend time together, doing what they love.

"I haven't seen her in a while and I miss her when I don't see her. I love her music," Knight said of LaBelle. "She supports me and whatever I do and I just wish we could pass that on to the rest of the world."

One way LaBelle is using her platform to support others is through her involvement in an upcoming charity event, a Virtual Disco Party benefitting Gabrielle’s Angel Foundation for Cancer Research, which streams on Tuesday, Sept. 15.

Due to COVID-19 precautions, this year's gala for the foundation was filmed remotely, and LaBelle was excited to participate, even if it wasn't an in-person event.

"I did it from my home with my background singers and my piano player," LaBelle recalled. "We had no place else to do it but home, you know, so we did it, and it was wonderful!"

Coronavirus concerns also necessitated safety protocols for Sunday's Verzuz, and both icons said they underwent COVID-19 tests -- along with their entire teams -- days before the event.

Because of the added precautions, Warwick's big surprise appearance almost didn't happen.

"We didn't think she was gonna be able to come" Knight shared. "Me and Patti had gotten together and Patti said, 'Yeah, I'm a do it, I'll be there.' But I hadn't gotten Dionne cleared yet."

Luckily for everyone who lost their minds on Twitter, Warwick managed to make it and turned a wonderful night of music into something truly historic.