Chelsea manager Thomas Tuchel appears to have opted for a 3-4-3 formation with three changes from last week’s first-leg.

Edouard Mendy starts in goal with Thiago Silva, replacing Andreas Christensen, Antonio Rudiger and captain Cesar Azpilicueta in defence.

Reece James plays at right wing-back with Ben Chilwell on the other side while Jorginho and N’Golo Kante, on for Mateo Kovacic, link up in midfield.

Mason Mount, Kai Havertz and Christian Pulisic, who takes Timo Werner’s place, lead the attack

And, Porto manager Sergio Conceicao appears to have opted for a 4-5-1 formation with one change from last week’s first-leg.

Agustin Marchesin starts between the sticks with Wilson Manafa at right-back and Zaidu Sanusi on the other side, while Chancel Mbemba and captain Pepe team up at centre-back.

Jesus Corona covers the right flank with Otavio on the left, whereas Sergio Oliveira, on for Luis Diaz, Liverpool loanee Marko Grujic and Mateus Uribe link up in midfield.

Moussa Marega leads the attack on his own