Dortmund have lost new signing Giannis Konstantelias to a significant knee injury, and Nwaneri is now expected to arrive in Germany for a medical and to complete the move before the Bundesliga transfer deadline at 19:00 BST. The 19-year-old forward had a loan spell at Marseille during the second half of last season and has attracted interest from clubs across the Premier League and Europe during this summer's window.
Arsenal's manager Mikel Arteta has an abundance of attacking talent, and Nwaneri would probably have had limited opportunities at the club this season. The Gunners academy graduate is expected to benefit from increased game time at another club, and Dortmund are set to sign him on a season-long loan.