The first leg kicks off in Turkey at 18.30 UK time, you can check the line-ups here.
This represents the first competitive match under new coach Mourinho, with the return leg next Thursday at the Stadio Olimpico.
“We are more of a unit and work as a team, but we’re also more determined to do well and I think that showed in pre-season, as we never gave up even in friendlies,” Pellegrini told Sky Sport Italia.
“We worked on our mentality, which has to be winning. Because Mourinho arrived and raised the bar, we must all develop the mentality that can get us used to winning.
“We can only do that one game at a time, playing every match as if it were our last.”
Pellegrini was forced to pull out of the Italy squad for UEFA EURO 2020 due to injury.
“I feel that I have improved as a player and try to do what the coach asks.”