Arsenal coach Mikel Arteta is likely to recall striker Pierre-Emerick Aubameyang to the starting line up after dropping him against Slavia Prague in midweek.
Arsenal conceded a goal in the last minute against the Czech side, however Arsenal's goal was assisted by Aubameyang, for Pepe, which still gives the north London side hope of making it into the semi final.
Martin Odegaard is expected to miss out through injury, but can make it back for the second leg in Prague next week.
Arteta could prioritise the Europa League over the Premier League, so changes should be expected against Sheffield United.
The continued absence of David Luiz means Rob Holding and Gabriel will be the centre-back pairing.
Calum Chambers will likely continue to take Hector Bellerin's place on the right.
Kieran Tierney is also expected to miss the clash due to injury. Cedric Soares should replace the Scotsman.
In midfield, Mohamed Elneny is expected to place Thomas Partey. Elneny is expected to play alongside Granit Xhaka, Dani Ceballos, Nicolas Pepe and Bukayo Saka
In attack, Alexander Lacazette started against Slavia Prague in midweek, but it's thought that he will be dropped for the returning Aubameyang.