Rafa Benitez makes just one change following his side's victory over Arsenal on Sunday as they chase a 2-0 defeat from the first leg at Stamford Bridge earlier this month
Michael Laudrup's side head into the fixture with the 2-0 first-leg victory they secured at Stamford Bridge on January 9.
Chelsea manager Rafa Benitez has made just one change from the side which ran out 2-1 winners over Arsenal in the Premier League on Sunday, with Ba being preferred to Torres in attack.
Swansea City sealed a 3-1 win over Stoke City in the Premier League on Saturday and Laudrup has made three changes from that starting side. Gerhard Tremmel replaces Michel Vorm in goal, while Garry Monk and Italy Shechter also drop to the bench as Chico Flores and Leon Britton return.
Swansea City: Tremmel, Rangel, Williams, Chico, Davies, Britton, De Guzman, Ki, Routledge, Hernandez, Michu
Subs: Vorm, Monk, Tiendalli, Lamah, Dyer, Shechter, Graham
Chelsea: Cech; Azpilicueta, Cahill, Ivanovic, A. Cole; Ramires, Lampard; Hazard, Mata, Oscar; Ba
Subs: Turnbull, Luiz, Ferreira, Terry, Bertrand, Marin, Torres.