Dave Johnson’s 20th minute header was the difference between the side though the Bloods were good value for their lead at a ground where the home side have taken several notable scalps in recent years in cup competitions.
Heavy rain left the pitch heavy and more fell during the half with Droylsden looking more comfortable on it and playing some excellent football.
The Stags side, last year’s Trophy finalists, showed two changes with Kelly making a debut at left back in place of Freeman, who was rested with a slight hamstring strain, and Verma returning from illness in midfield at the expense of Bolland.
Players struggled to keep their feet on the sodden surface in the early stages.
Gardner did well to get round Thompson on the right but there was no one there to profit from his intelligent pull-back.
Then Marriott needed two bites of the cherry to hold on to a stinging 20 yard shot from Johnson.
But it took a great stop from home keeper Phillips on 10 minutes to deny Green.
Stevenson capitalised on a slip by Holden to pull back a cross from the right which saw Green shape to meet it on the volley and fire in a great on-target finish which Phillips beat away and was then relieved to see Meikle blaze the loose ball over the top.
Brown also rifled a good shot over from a tight angle on the right when the home side suddenly had men over.
At the other end, a Mansfield counter-attack ended with Stevenson shooting low across the face of goal as the brain came down sharply again.
But on 20 minutes Stags found themselves in arrears as the Bloods went ahead via route one. Langford sent a long free kick down the centre where Johnson rose to nod a firm header past Marriott from 12 yards out.
Marriott was back in action to grab a decent Marshall free kick after Murray had conceded the foul 20 yards from goal.
Then Phillips safely held on to a Stevenson cross after Sutton had caught Hall in possession trying to play the ball out his own box.
A great pass from Gardner sent Holden on the overlap down the left and his low cross came off Sutton’s heel at the near post and passed inches wide for a corner.
The home side produced another good move own the centre from which Rowe, with Stags unable to dispossess him, eventually fired too high.
Dempster and Johnson were involved in a tugging match 20 yards from goal and when Dempster had the final tug to send Johnson to the turf, the Stags man was booked on 31 minutes and Rowe blasted the subsequent free kick into the wall.
Marriott again had to get it right as a low 20 yard Rowe shot skidded in precariously on the wet surface towards him, the keeper getting his body fully behind it.
Droylsden again waltzed through the middle of the Mansfield rearguard just before the break and Hall set up Gardner for a shot Marriott beat away and when Killeen followed-up, again Marriott was there as Stags went in glad to only be one goal in arrears.
DROYLSDEN: Phillips, Brown, Holden, Langford, Kerr, Marshall, Killeen, Hall, Rowe, Johnson, Gardner. Subs: Kilheeney, Peyton, Gerrard, Rouse, Lake.
STAGS: Marriott; Sutton, Dempster, Thompson, Kelly; Murray, Verma, Stevenson; Dyer, Green, Meikle. Subs: Briscoe, Rodney, O’Neill, Bolland, Redmond.
REFEREE: S. Martin of Stafford.