A police officer who is also a former American Idol contestant gave an incredible impromptu performance of the national anthem when the scheduled singer got stuck in traffic.

Officer Carlton Smith dazzled the crowd as he sang a storming version of the Star-Spangled Banner on Tuesday night, kicking off the college basketball game between West Virginia University and the University of Kansas.

In video capturing the knockout performance, the crowd is seen erupting into cheers and applauding Smith as he walks from the middle court after singing.

Officer Carlton Smith gave an incredible impromptu performance of the national anthem on Tuesday night when the scheduled singer got stuck in traffic

Smith dazzled the crowd as he sang a storming version of the Star-Spangled Banner on Tuesday night, kicking off the college basketball game between West Virginia University and the University of Kansas

'Any chance I get to do the national anthem is always a big deal to me,' Smith told Inside Edition as he recalled his performance.

'I was just basically hoping I didn't mess it up too much.'

Smith had been working security during the game in West Virginia, but stepped in to sing with only a five-minute notice after singer Leslie Dorchester could not make it due to a snowstorm, Inside Edition reported.

Dorchester said she was devastated she was unable to make it for her scheduled performance that night.

Smith had been working security during the game in West Virginia, but stepped in to sing with only a five-minute notice after singer Leslie Dorchester (pictured left and right) could not make it due to a snowstorm

Following his knockout performance, people from the crowd were seen applauding the police officer

Smith was chosen to sing the national anthem after someone remembered he had auditioned for American Idol in 2014

'I tried so hard to get there. I actually parked my car and tried to run in the snow and ice,' she told Inside Edition.

However when she failed to make it, someone remembered Smith he was a 2014 American Idol contestant.

On Friday, Dorchester wrote on Twitter that 'sometimes good things happen to those who are late'

'They were like, "Hey, we need a favor. Can you sing the anthem?" I said, "how long do I have?" They said "about five minutes,"' Smith told Inside Edition.

While the West University graduate's day job is working as a police officer, singing is his passion.