Dortmund s Sebastien Haller celebrates after scoring his side s second goal during the German Bundesliga soccer match between FC Augsburg and Borussia Dortmund at the WWK Arena in Augsburg, Germany, Sunday, May 21, 2023. AP
Haller scored twice in Dortmund's 3-0 win at Augsburg, which took them two points clear of Bayern Munich with just one game to play.
The Ivory Coast striker missed the first half of the season as he battled testicular cancer, returning in January.
Since Haller's return, Dortmund have lost just one of 18 league matches.
"That he's back with us is a pure miracle" Terzic said after the game, praising the forward's "important" presence "in the dressing room".
Dortmund can seal their first title in a decade with a win at home against Mainz on Sunday and will also lift the trophy if they equal or better Bayern's result away at Cologne.
The manager said the 28-year-old Haller scores "important goals" but "also lets the others next to him shine".
Terzic said he hoped Haller would replicate his success next week "then he'll be the hero of the season. But we're already very happy with him anyway."
Dortmund sporting director Sebastian Kehl, who made the decision to bring Haller to the club from Dutch side Ajax, praised "Sebastien's special story. He deserves extra credit."
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