'OMG is that the bloke from East 17?': Bake Off fans gobsmacked as Tony Mortimer, 47, performs piano version of Stay Another Day on Christmas special

He is responsible for one of the most popular Christmas songs of all time, which remained at number one for five weeks back in 1994.

But viewers of The Great British Bake Off failed to recognise East 17's Tony Mortimer on Monday, as he performed Stay Another Day on the Christmas special. 

The singer, now 47, belted out a piano version of the famous hit with the help of the hosts, judges and contestants, to round off the festive episode of the Channel 4 show. 

Back again: Viewers of The Great British Bake Off failed to recognise East 17's Tony Mortimer on Monday, as he performed Stay Another Day on the Christmas special

Back again: Viewers of The Great British Bake Off failed to recognise East 17's Tony Mortimer on Monday, as he performed Stay Another Day on the Christmas special

Clad in a trademark white parka, complete with fluffy hood, Tony channeled his East 17 days as he performed the much-loved ballad in the famous Bake Off tent - with the judges and contestants singing along in front of the piano.

However, despite his recognisable singing voice, many viewers took to Twitter to express their confusion and shock over his appearance on the show.

One kicked things off by writing: 'OMG is it that bloke from East 17? #GBBO' while others added: 'No way! Is that Tony Mortimer?' and 'Whoa whoa whoa... tony is old! #gbbo #east17'

Worlds away: The singer, now 47, belted out a piano version of the famous Eats 17 hit with the help of the judges and contestants - which shot to number one in 1994 (pictured that year)

Worlds away: The singer, now 47, belted out a piano version of the famous Eats 17 hit with the help of the judges and contestants - which shot to number one in 1994 (pictured that year)

Here he is: Clad in a trademark white parka, complete with fluffy hood, Tony channeled his East 17 days as he performed the much-loved ballad in the famous Bake Off tent

Here he is: Clad in a trademark white parka, complete with fluffy hood, Tony channeled his East 17 days as he performed the much-loved ballad in the famous Bake Off tent

Other viewers chimed in: 'Actual Tony Mortimer on #GBBO' and 'Tony Mortimer KLAXON! #GBBO' 

While other disbelieving fans wrote in shock: 'WHAT THE HELL HAPPENED TO TONY MORTIMER' and '#GBBO was great. East 17 cross over was ... Unexpected.'

However, many East 17 supporters were quick to express their joy at his appearance, and confess they were still big fans of the group.

Everybody join in! The hosts, judges and contestants sang along in front of the piano, in a festive end to the Christmas special

Everybody join in! The hosts, judges and contestants sang along in front of the piano, in a festive end to the Christmas special

'OMG is that the bloke from East 17?': However, despite his recognisable singing voice, many viewers took to Twitter to express their confusion and shock over his appearance on the show

'OMG is that the bloke from East 17?': However, despite his recognisable singing voice, many viewers took to Twitter to express their confusion and shock over his appearance on the show

One wrote: 'Loved seeing @tony_mortimer on #GBBO #NewYearTreat #stillafan' while others added: 'Loving Tony Mortimer on The Bake Off!' and '@tony_mortimer great to see you on bake off.' 

His stripped back rendition of the ballad came after hosts Sandi Toksvig and Noel Fielding and judges Paul Hollywood and Prue Leith performed a parody of the hit, to open the festive episode.

Clad in matching white hooded coats, much like the band in the music video, the foursome hilariously transformed into Yeast 17, and pretended to perform the song.

The sketch left viewers in hysterics, with one stating on Twitter: '@noelfielding11 @PrueLeith @sanditoksvig @PaulHollywood doing ‘stay’ by east 17 has just made my day !! Noel was just g****m majestic swirling in that white cape/fabricstorm . Just wow' (sic) 

Big fans: However, many East 17 fans were quick to express their joy at his appearance, which celebrated the New Year on Channel 4

Big fans: However, many East 17 fans were quick to express their joy at his appearance, which celebrated the New Year on Channel 4

Yeast 17: His rendition of the ballad came after hosts Sandi Toksvig and Noel Fielding and judges Paul Hollywood and Prue Leith performed a parody of the hit, to open the episode

Yeast 17: His rendition of the ballad came after hosts Sandi Toksvig and Noel Fielding and judges Paul Hollywood and Prue Leith performed a parody of the hit, to open the episode

Smashed it: The sketch left viewers in hysterics, who took to Twitter to praise the comic moment

Smashed it: The sketch left viewers in hysterics, who took to Twitter to praise the comic moment

Others were quick to agree, writing: 'I could easily watch Paul, Prue, Noel and Sandi re-enact East 17 for an hour' and even '#GBBO does East 17 is already the highlight of 2018.'

Stay Another Day was the Walthamstow-based band's only chart-topping single - but it remained in the top spot for five weeks in 1994, and was the Christmas number one of that year.

The hip-hop troupe also found success with their hits House Of Love, It's Alright and If You Ever, a duet with Gabrielle, before they split amid a drug controversy in 1997.

The band briefly reformed in 2006 and 2010, but Tony has since embarked on a new career as a record producer at his studio in Essex.

Back in the day: Stay Another Day was East 17's only number one single, but has become one of the most beloved Christmas songs (bandmates Brian Harvey, Terry Coldwell, Tony and John Hendy L-R)

Back in the day: Stay Another Day was East 17's only number one single, but has become one of the most beloved Christmas songs (bandmates Brian Harvey, Terry Coldwell, Tony and John Hendy L-R)

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