Alexa PenaVega will not be returning to season 21 of the ABC reality dance competition

By Patrick Gomez
Updated November 12, 2015 09:00 PM
Credit: Craig Sjodin/ABC

The show must go on.

After Tamar Braxton withdrew from season 21 of Dancing with the Stars earlier this week because of blood clots in her lungs, the ABC reality dance competition’s producers looked "at all possibilities" (including bringing back recently eliminated star Alexa PenaVega), but ultimately it was decided only the remaining four couples will compete on Monday’s episode, PEOPLE can reveal exclusively.

To fill the time that had been slotted for Braxton’s performances, the semi-finalists will dance head-to-head in a competition that was just added to the lineup for Monday.

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For the dance-off challenge, Nick Carter and partner Sharna Burgess will dance a samba against Bindi Irwin and partner Derek Hough.

And Alek Skarlatos and partner Lindsay Arnold will dance a cha-cha against Carlos PenaVega and partner Witney Carson.

The judges will score the dances and each couple that wins the dance-off challenge will be awarded three points.

These points will be added to the points received for the two previously scheduled dances the couples have been preparing: one featuring a dance style they have not danced yet this season and another as a trio featuring a second pro dancer of their choosing.

Skarlatos and Arnold will dance a waltz to “America The Beautiful” performed by the house band Ray Chew Live and will dance their trio dance with the train hero‘s crush, Emma Slater, whose partner Hayes Grier was eliminated week seven.

Irwin and Hough will dance a salsa to “You’re Never Fully Dressed Without a Smile” by Sia and chose Mark Ballas – who had been partnered with Alexa – to complete their trio.

Carlos and Carson will do a contemporary to “Drag Me Down” by One Direction and will dance their trio dance with Karina Smirnoff, whose partner Victor Espinoza was eliminated in week two.

Carter and Burgess will dance a tango to “Scars” by Alesso feat. Ryan Tedder and will be joined for their trio dance by Peta Murgatroyd, who had been partnered with Andy Grammar but had to drop out before the season began because of an injury.

There has been no official decision made as to whether someone will be eliminated at the end of Monday’s episode.

Dancing with the Star airs Mondays (8 p.m. ET) on ABC.