Union Berlin, 2.08.
Regensburg won their opening game of the new season, a 3-1 away victory against Munich 1860, but since then haven't won in four. They scored 2 last time out away to Heidenheim, but failed to score in three consecutive home games before that. Looking a little further into this, Regensburg haven't won a single game at home in 17 matches, when they defeated St.Pauli 3-0 in September of last year!
Union haven't won in three, but they had an encouraging club friendly start to the season. Out of 7 matches they won 5 including a 3-0 win over Celtic. They lost to Bochum in the opening league of the season 1-2, and drew to Bielefeld 1-1 second match, but they are scoring goals. They have only lost once both home and away in their last 11 games. I think with Union being able to score, and Regensburg only finding the net twice in four games (including NONE at home so far this season) then the odds of 2.08 for an away win for a side in a higher division represents decent value.