Borussia Dortmund have a slim advantage over Atalanta after winning the first leg 3-2 and will definitely reach the UEFA Europa League Round of 16 with a win or a draw in the return meeting. If they lose, the winner of the tie will depend on the number of away goals scored.

Atalanta will go through with...
a 1-0 win
a 2-1 win
or a win by a margin of more than one goal

Dortmund will go through even with...
a 4-3 defeat
or any other defeat by a single goal in which they have scored at least three themselves

There will be extra-time if...
Atalanta after 3-2 ahead after 90 minutes

There will be penalties if...
Atalanta are still 3-2 ahead after 120 minutes

Borussia Dortmund's record in penalty shootouts:
2 wins (1992/93 against AJ Auxerre, 1999/2000 against Rangers)
2 defeats (2003/04 against FC Brugge, 2008/09 against Udinese) (br)