But the club have lost patience with the Bundesliga outfit after Oxford's failure to break into their first team despite having the second worst defensive record in the league so far this season.
Oxford, who shot to prominence when he made his debut with a midfield masterclass in a 2-0 win over Arsenal at the Emirates in the opening game of the 2015/16 season aged just 16, is said to be 'massively disappointed' with his loan experience, as reported by The Sun.
The report claims he will not return until December which is the halfway point of the season-long deal.
West Ham United boss Slaven Bilic talks to Oxford
It seems the earliest West Ham could call on Oxford will be in December/January at the earliest, the folly of which would be brought sharply into focus should West Ham suddenly suffer a defensive injury crisis.
It is the latest negative twist in the hot prospect's fledgling career so far and comes after he signed a long term deal with the Hammers to ward off very real interest from some of Europe's top clubs keen on securing his signature.