Kane Brown and Lauren Alaina joined forces onstage at the 2018 ACM Awards to perform their collaboration "What Ifs." The song became a No. 1 hit -- Brown's first -- after its release as a single.

Brown opened the song against a rocky ocean backdrop, sing-talking through the verse's signature spoken word style. The real power came when Alaina emerged, entering the stage as the song took a dramatic crescendo into the chorus. The powerhouse duo gave a gripping live performance that looks some of its cues from the song's music video.

"What Ifs" received a nomination for Vocal Event of the Year at the 2018 ACM Awards. The song helped establish Brown as an artist at country radio, and it boosted Alaina's career around the time her single "Road Less Traveled" was earning success.

In addition to Vocal Event of the Year, Brown was nominated for New Male Vocalist of the Year at the 2018; he lost the award narrowly to fellow newcomer Brett Young. Alaina, however, scored a win in the New Female Vocalist of the Year category.

2018 ACM Awards: All the Red Carpet Looks

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