Derbyshire has scored four times in 10 appearances since joining the Latics in September, but his initial loan at Boundary Park expired after the weekend's 1-1 League One draw at Crawley.
The 26-year-old is unlikely to feature in Saturday's FA Cup first-round tie with Kidderminster, with Oldham boss Paul Dickov expected to wait until the league derby with Bury a week on Tuesday to extend the deal in order to maximise the 93 days Derbyshire is allowed to remain with his club under the emergency loan system.
"It is a matter of whether we renew Matt's loan before or after the FA Cup tie," Dickov told the Latics official website.
"We have to work out dates. If he plays on Saturday, he will have to go back in mid-December.
"If we can work it right, though, he will be here to January."