Kang Min Kyung expressed her disappointment in her performance for SPEED's debut stage and offered her apologies to the members of the rookie group.

The Davichi member stood on stage with SPEED for their official debut stage for the opening segment with "Sad Promise". During the stage, she experienced her voice cracking at one of the notes, which is said to be a first for her since debut.

Feeling bad about her slight waver in pitch, instead of going out to the dinner that she had planned to treat the members to afterwards, she canceled the event and offered apologies to SPEED, commenting, "I wanted to do so well, but I'm so sorry... I'll make sure not to harm the stage of the SPEED members in the future."

Seeing her frustrated over the slight mistake, the SPEED members tried to console Kang Min Kyung, and apologized to her in return: "We're really sorry because sunbaenim had her first mistake while she was trying to help us. We'll become a SPEED that continues to work hard."

The performance can be seen below.