Gallant版本的《Only One》是一首忠于原曲旋律但以更加安稳舒适的感觉加以表现的歌曲。此外也维持了甜中带苦的原曲歌词感性，节奏上融入了正向积极的Vibe，欲为正在经历离别的失落感的人们传递温暖慰藉。

[Credit]
Executive Producer: SM ENTERTAINMENT Co., Ltd.
Producer: SOO-MAN LEE
Music & Sound Supervisor: YOO YOUNG JIN

Music Produced by lophiile, Darion Ja'Von Dean
Directed by Gallant
Background Vocals by Gallant
Guitar Performed by Luke Aiono
Bass Performed by Darion Ja'Von Dean
Drums Performed by Trenell Reid
Piano Performed by Timothy Manson
Engineered for Mix by 강은지 @ SM SSAM Studio
Mixed by 구종필 @ KLANG Studio
Mastered by 권남우 @ 821 Sound Mastering