Defender Mavropanos, 20, was signed from Greek side PAS Giannina last week for a reported fee of £2.2.m having been recommended by the club's new head of recruitment Sven Mislintat.
After confirming the move, Wenger said the Greek youngster would immediately leave the club on loan, recently telling reporters his side's latest acquisition "is not ready to play for us."
It was widely reported a loan switch to Bundesliga strugglers Werder Bremen had been lined up but with a spate of injuries crippling Wenger's first-team options, those plans could be delayed.
The first-choice trio of Laurent Koscielny, Nacho Monreal and Sead Kolasinac remain injured ahead of Wednesday's trip to Stamford Bridge with none of the three to have featured this year. Shkodran Mustafi meanwhile will undergo a late fitness test after picking up an unspecified knock.
Wenger selected Mathieu Debuchy, Per Mertesacker and Rob Holding for Sunday's FA Cup third round clash against Nottingham Forest with Calum Chambers, the manager's only other defensive option rested, but that starting back-three endured a woeful afternoon at the City Ground with Debuchy and Holding both giving away penalties in a 4-2 defeat.
Mavropanos, who made 14 appearances for PAS Giannina in Greece's Super League before heading for England, was pictured in first-team training sessions this week and the Guardian also report the youngster is now set to be named among the Arsenal substitutes in west London on Wednesday night.
With his defensive options limited, Wenger also faces selection headaches elsewhere with Aaron Ramsey and Olivier Giroud still ruled out. Latest reports suggest Mesut Ozil is also back on the injured list, with Granit Xhaka another who will have a late fitness test ahead of kick-off.