Everton starting line-up: Stekelenburg; Holgate, Keane, Jagielka, Baines; Schneiderlin, Besic; Vlasic, Rooney, Sigurdsson, Calvert-Lewin.
Everton substitutes: Pickford, Williams, Ramirez, Mirallas, Martina, Gueye, Klaassen.
Everton kick off their Europa League group stage campaign this evening, as they take on Serie A side Atalanta at the Stadio Atleti Azzurri d'Italia.
Koeman has surprisingly switched his goalkeeper, as Maarten Stekelenburg replaces Jordan Pickford in goal, whilst Mason Holgate, Michael Keane, Phil Jagielka and Leighton Baines all start across the back four.
Morgan Schneiderlin is partnered by Muhamed Besic in holding midfield, whilst there is a start for new signing Nikola Vlasic, who will feature on the right of midfield.
With Gylfi Sigurdsson on the left, Wayne Rooney will play behind Dominic Calvert-Lewin in the final third, as Everton look for European success after beating Ruzomberok and Hajduk Split in the qualifiers.
Pickford is dropped to the bench alongside Ashley Williams, whilst the likes of Sandro Ramirez, Kevin Mirallas, Cuco Martina, Idrissa Gueye and Davy Klaassen.