B1A4's Sandeul stood on stage alone, without the help of fellow members Baro and CNU, for the first time on 'Immortal Song 2'.

The November 17th episode featured the music of legendary singer Lee Yong. Sandeul started his rendition of the song "Forgotten Season" smoothly, but was disappointed when his voice cracked in the middle of the performance.

Afterwards, host Shin Dong Yup asked Sandeul how it felt when his voice cracked, and he answered, "I was [disappointed]. It started out the way I wanted, but then [I lost it]."

Son Ho Young, who beat Sandeul by 6 points,�eventually grabbed first on this episode.

Check out Sandeul's performance below!