The Gunners have won both of their opening fixtures in this year's group stage while fielding a side packed with youth products, scoring seven goals and keeping two clean sheets in the process.
Vitoria, who had to come through three play-off ties to make this round of the competition, have lost their opening two matches without finding the net.
Here, Sports Mole looks at how Arsenal could line up for Thursday's showdown.
Out: Reiss Nelson (knee)
Unai Emery is likely to send out a much changed team for Thursday's game, much as he has in their previous matches with Standard Liege and Eintracht Frankfurt.
As such, cup keeper Emiliano Martinez will return to take up his brief between the sticks with Rob Holding leading the defence alongside Shkodran Mustafi, summer signing Kieran Tierney and Ainsley Maitland-Niles.
Uruguayan Lucas Torreira, a regular Premier League starter last season, is likely to sit at the base of the midfield alongside the Spaniard Dani Ceballos, who the Gunners will look to as a regulator and creator from deep.
Although they all played in the North London club's 1-0 defeat against Sheffield United on Monday, Bukayo Saka, Joe Willock and Nicolas Pepe are set to continue behind the striker as they look to build a strong attacking relationship.
Top scorer Pierre-Emerick Aubameyang is likely to be rested and, while Alexandre Lacazette was fit enough to come on as a substitute against the Blades, young Brazilian striker Gabriel Martinelli is expected to lead the line after nabbing four goals in his first two starts for Arsenal.