In JTBC’s Sing Again 4, Round 2 featured era-classic team battles between paired contestants.

On the November 4 episode of JTBC’s Sing Again 4, the Round 2 “Era Classics” team battles saw two duos take the stage: 40호×75호 with the team name Moms on Top, and 17호×67호 with the team name Do Over Again. Moms on Top performed Lee Jang-hee’s That’s You, while Do Over Again chose Eunha’s Night Ride. The pairing of 17호 and 67호, under the name Do Over Again, delivered a performance that sparked strong reactions from the judges.

The judges’ feedback highlighted the energy and dynamics of the performances. Kyuhyun noted that their group background didn’t show, praising the choreography and rhythm, while Haeri commented that the two felt like a true team and managed the complex arrangement with stability. In the end, Do Over Again received unanimous praise, securing the victory and advancing to the next round.

Following the result, Moms on Top faced elimination: there would be no additional qualifiers for that pair. The 40호 contestant was revealed as Jeon Hye-sun, and the 75호 contestant was identified as Bona from Sharkra before leaving the stage.