Newton picked up his fifth booking of the season on 9 December
Droylsden could be thrown out of the FA Cup after allegations that they fielded an ineligible player in their shock second-round win over Chesterfield.
Sean Newton scored both goals as the non-league club stunned their League Two opponents in a 2-1 win on Tuesday.
But Chesterfield asked the Football Association to intervene when they discovered Newton should have been serving a one-match ban on 23 December.
Bury were expelled from the competition in 2006 for a similar offence.
In that incident, Stephen Turnbull played in Bury's second-round tie against Chester, who were reinstated and faced Ipswich in the third round.
Droylsden's case will be discussed at an FA Cup committee hearing on 29 December.
"The FA can confirm it is making enquiries into Droylsden's apparent fielding of an ineligible player in their FA Cup second round tie against Chesterfield," read an FA statement.
"The enquiries relate to defender Sean Newton, who picked up his fifth booking of the season on 9 December.
"According to the FA's disciplinary regulations, he was therefore suspended for one match from Tuesday, 23 December.
"Droylsden were informed of the suspension on 10 December, which was then confirmed by the club four days later. Clubs are aware that they are responsible for checking that their players are eligible to play in any given match."
Bloods manager and chairman Dave Pace said the club sent a fax to the FA after being told of the suspension and explained that as far as they were concerned, Newton would serve his ban in their league game on Boxing Day.
"If there was any doubt from our point of view that he should not have played against Chesterfield then he would not have," he told BBC Radio 5 Live.
Pace admitted he was shocked when being told his side may not be able to play in the third round tie at Ipswich on 3 January.
"If that happens I will go to the nearest bridge and throw myself off. I just can't believe it," he added.
The second-round match between the two sides had been twice abandoned because of fog and floodlight failure, in between a controversial 2-2 draw at Saltergate.
Droylsden had protested furiously when Jack Lester put Chesterfield 2-1 up when he lobbed the keeper from a throw-in after the visitors had put the ball out of play for an injured player.
The home side then allowed Steve Halford to walk unchallenged into their half to tap the ball in for the equaliser.