Mkhitaryan was instrumental in Thursday's victory in Sweden, his cross being put into the net by Papagiannopoulos before providing the assist for Ozil to fire home the third.
"It was their first game after a while, because we are in the league and keep playing maybe we are more practiced," the Armenian told BT Sport at full time. "They are a good team, tried to play, but we scored two in the beginning."
When asked if the Gunners can win the Europa League, he replied: "Why not? We have to keep fighting, in the end see where we're at. We have to focus on every game regardless of this result to ensure more success. Even with the League Cup final, I think we have to play with the same team and win at home."
The second leg of the last-32 tie takes place at the Emirates Stadium next Thursday before Arsenal go on to face Manchester City in the EFL Cup final three days later.