Dortmund are looking to overturn a 1-0 defeat from the first-leg when Kostas Mitroglou scored Benfica's winner.
Borussia's star striker Pierre-Emerick Aubameyang had a night to forget in Lisbon with four missed chances.
Guerreiro is on the bench for the second leg, dropping out of the starting side with a thigh injury, and Gonzalo Castro takes his place.
USA teenager Pulisic replaces Reus, who is sidelined until April with a hamstring injury.
Benfica coach Rui Vitoria has made two changes from the team which beat Fierense on Saturday in the Portuguese league. Winger Franco Cervi started up front and Nelson Semedo came into the defence.
Mitroglou, who was raised in Germany, has scored 18 goals in his last 17 games while Aubameyang has 21 goals in as many German league games.
Starting line-ups for the Champions League last-16 second-leg tie between Borussia Dortmund and Benfica at Signal Iduna Park on Wednesday (kick-off 1945 GMT, Benfica lead 1-0 on aggregate):
Borussia Dortmund: (3-4-2-1) Roman Burki; Lukasz Piszczek, Sokratis Papastathopoulos, Marc Bartra; Julian Weigl, Gonzalo Castro, Erik Durm, Marcel Schmelzer (Capt); Ousmane Dembele, Christian Pulisic; Pierre-Emerick Aubameyang
Coach: Thomas Tuchel
Benfica (4-4-2): Ederson; Nelson Semedo, Luisao (capt), Victor Lindelof, Eliseu; Eduardo Salvio, Andreas Samaris, Pizzi, Andre Almeida; Franco Cervi, Kostas Mitroglou
Coach: Rui Vitoria
Referee: Martin Atkinson (ENG)