The 22-year-old was introduced from the bench to score his side’s second goal in the 50th minute after Jacob Bonde opener in the 25th minute.
Jatta has featured in all 10 Danish Superliga games for Viborg so far this season.
He is yet to score a single goal for Viborg in the Danish Superliga this season after 10 matches.
Viborg sit 9th position in the Danish Superliga table with 16 points after 15 games, while St. Pauli leads the German Bundesliga 2 with 26 points after 12 matches.