The youngster joined Hoffenheim on a season-long loan.
Nelson made an immediate impact as he scored on his debut just 15 minutes after coming off the bench.
And the 18-year-old is clearly out to impress after scoring twice to earn his side a valuable win.
Hoffenheim were losing 1-0 up until the 50th minute when Nelson fired in an equaliser.
He then took just another seven minutes to net his second of the match.