A noughties rockstar looks so unrecognisable a fan belting out one of his songs didn't even notice he was standing right behind her.

The rocker rose to fame in the early 2000s as the lead singer, guitarist and songwriter of an American band that formed in Texas. But the musician, now 51, looks so different that when he surprised a fan in a viral TikTok video she struggled to realise it was him.

In the clip, the star could be seen at the Blockhouse Sports Bar in Elk City, Oklahoma, and was standing behind a woman as she sang along to a song that was playing. The video was captioned: "When singing your heart out and don't know the artist is behind you."

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If you've not guessed it by now, the artist is Jaret Reddick from Bowling for Soup. The TikTok, originally shared by the sports bar, showed fan Brittiny Freeman singing along to the band's hit song Girl All the Bad Guys Want.

Jaret, who was wearing a black t-shirt and a pair of black-rimmed glasses, can be seen getting up from his seat behind her and approaching the camera as he joins in with the singing. He continues to get closer and closer to the fan while singing along with her but she appears to be completely oblivious to his presence.

At one point the pair even ironically sing the lyrics "she doesn't even notice me" together. But as Jaret comes to stand right beside Brittiny he finally spots him.

When she first looks at him she makes a puzzled expression before her eyes suddenly widen as she appears to finally realise who's stood next to her. The pair continued singing along together as she laughed.

Jaret found the video so funny he even shared it himself, he captioned his Instagram post of the clip: "Fun night at @blockhouse_sportsbar ! She had no idea!!!" Some fans weren't surprised she didn't recognise him at first.

"Tbf, even I didn't recognise him and I probably wouldn't have if you didn't tell me," one person wrote. Another agreed, adding: "To be honest I wouldn't have recognized him either after 20 years."

A third said: "Not surprised she didn't realise tbf hahaha." But others thought it was crazy it took her so long to realise and were shocked by her calm reaction.

"This is wild. Dude is singing it with her and the light never came on," one fan wrote. A second said: "That's amazing lol I’d just pass out, not even continue singing. Just pass out."

A third commented: "So freaking awesome! I would literally fan girl out at that moment. You’re awesome, man!" Bowling for Soup were formed in 1994 in Wichita Falls, Texas, where Jaret grew up, and made their first major label debut in 2000.

The band originally consisted of Jaret, Chris Burney, Erik Chandler and Lance Morrill, who left the band on good terms in 1998 and was replaced by drummer Gary Wiseman.

As well as Girl All the Bad Guys Want, the band are known for singles including 1985, Almost and High School Never Ends. They're also known for performing the theme song to the Disney Channel show Phineas and Ferb.

The band are still together, although Erik left Bowling for Soup in 2019 and was replaced by Rob Felicetti. They are set to embark on a US and UK tour next year, where they're scheduled to perform in Key West, New Orleans, Orlando and Miami Gardens in the US, and London, Manchester, Leeds, Newcastle, Hull, and Glasgow in the UK.