K-pop fans were treated to a special moment in the latest episode of 'Synchro U,' when Jay Park and SHINee's Onew took the stage for a duet.

'Synchro U' is a unique music variety show where top artists perform cover stages along with AI-generated vocals, and the panelists must guess which cover tracks were sung by the actual singers. 

In the latest episode, Jay Park and SHINee's Onew surprised viewers and fans when they appeared on stage while singing CRUSH's "Sometimes."

Fans were quick to express their excitement, with many praising the unexpected collaboration. Many noted that it's been over a decade since the two idols were seen together.

Translation: "Never thought I'd live to see an Onew and Jay Park duet. This is so cool."

Translation: "It feels like the first time seeing Onew and Jay Park together since the show 'She's Here.' It’s been such a long time."

Moreover, Korean netizens were impressed with the vocal chemistry between the two artists and were ecstatic to see them together again after many years.

Korean netizens commented:

"When was 'She's Here' even, LOL. It's been forever!"

"I knew Onew was great, but I didn't realize Jay Park was this good at live singing. After watching this performance, I gained a whole new level of respect for him. Plus, their voices blend so well together. I really hope they release this as a track."

"Their vocal chemistry is insane… and wow, Jay Park can really sing."

"Both were known for their unique voices, but watching this makes me appreciate them even more."

"This is seriously amazing, it’s so good."

"What’s up with their voice combo? It’s just too good."

"Their vocal blend is insane."

"When Yoo Jae Suk said 'oh, so good,' I actually said it out loud too, LOL."

"Seeing them together for the first time since 'She Came'—this is really soulful and sweet."

"Their voices together are just unbelievable, seriously."

"It’s an unexpected pairing, but it feels nostalgic and heartwarming in so many ways… I love it."

"This is crazy. These two have such unique voices, but together, it’s pure magic."

SEE ALSO: Jay Park drops moody trailer for 'THE ONE YOU WANTED'