Luiz, who was taken off with a hamstring injury against Newcastle United last weekend, was not in the squad that drew with Villarreal on Thursday and the Brazilian is unlikely to feature against the Baggies.
Meanwhile, Xhaka was due to start their second-leg semi-final tie in the Europa League before picking up a muscle strain in the warm-up. Mikel Arteta is hoping that the versatile Switzerland international can recover in time for this weekend.
Left-back Kieran Tierney and striker Alexandre Lacazette were both doubts for the midweek fixture but did feature, with the latter coming on from the bench. Whether the Scotsman and the Frenchman are fit enough to play 90 minutes remains to be seen, but both players should be in contention to start.
Midfielder Dani Ceballos is available to play on Sunday, after the Real Madrid loanee was suspended for Thursday's game.
Progression to the Europa League final may have seen Arteta rotate his starting lineup for the remaining four Premier League fixtures, but the Spaniard is now more likely to name strong sides heading down the home straight if they are to keep their slim chances of European qualification alive.
Thomas Partey and Mohamed Elneny could dictate play from holding midfield positions, with Bukayo Saka and Nicolas Pepe operating on the flanks, while one of Emile Smith Rowe or Martin Odegaard is expected to start in the number 10 role.
Pierre-Emerick Aubameyang is set to lead the line once again in attack. The Gabonese forward, who scored against Newcastle last weekend, became the sixth Arsenal player to score more than 10 goals in each of his first four Premier League seasons with the club after Ian Wright, Dennis Bergkamp, Thierry Henry, Olivier Giroud and Lacazette.
Arsenal possible starting XI: Leno; Chambers, Holding, Gabriel, Tierney; Partey, Elneny; Saka, Smith Rowe, Pepe; Aubameyang
Watch the Sports Mole Football Shorts prediction for this game below: