The Venezuelan midfielder scored an incredible 50-yard goal in his side's 2-0 win over Mainz on Sunday, to add another fine effort to his growing catalogue of spectacular strikes, leading to praise from his coach.
"Juan is one of the best left-footed players in the world," Favre told reporters.
"His goal at the weekend was the goal of the year. I was wondering for ages whether the ball would go in, and it did. He has been scoring some incredible goals this season, the one against Frankfurt and the one against Wolfsburg."
Gladbach striker Luuk de Jong was also quick to hail his team-mate's prodigious talents and noted his ability to manipulate the flight of the ball as one of his key weapons.
"Juan is capable of scoring these kinds of goals and he shows that all the time in training. He hits them in such a way that they bend in different directions in flight," he added.
Arango has scored five goals in 16 Bundesliga appearances this season.