The Blues were beaten 1-0 by the Championship side in the first leg two weeks ago and now have the task of turning things around.
Mauricio Pochettino's side have found some form in the Premier League but defeat to Boro has put them on the brink of a shock exit.
Michael Carrick will be delighted to be heading to Stamford Bridge ahead in the tie but his team face a tough task to secure a spot at Wembley.
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Chelsea XI: Petrovic, Disasi, Silva, Colwill, Chilwell, Caicedo, Fernandez, Mudryk, Palmer, Sterling, Broja.
Subs: Bergstrom, Curd, Badiashile, Gilchrist, Gallagher, Chukwuemeka, Castledine, Madueke, Washington.
Middlesbrough XI: Glover, Engel, Van den Berg, Fry, Clarke, Barlaser, Hackney, Howson, Crooks, Forss, Rogers.
Subs: Jones, Gilbert, Dijksteel, McNair, Coburn, O'Brien, McCabe, Bridge, Bilongo.
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