Spurs were leading 2-0 in the UEFA Youth League clash, but poor Austin allowed Dortmund back into the contest with a misake he'll want to forget as quickly as possible.
In the 29th minute, a flowing BVB move led to Emre Aydinel taking a hopeful shot from range which forced Austin into action.
At first it looked like the young net-minder had a grasp on it, but the ball ended up squirming underneath the young American as he landed, and then rolling agonisingly beyond the line.
Austin's name was attributed with the goal – but fortunately for the 18-year-old, Tottenham went on to win the contest 3-1 in Germany.
Spurs' youngsters lead Group H with one group match remaining, one point clear of Dortmund and three ahead of third-placed Real Madrid.
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