Inspectors from the Football Association will look at the ground this morning following an official complaint by Scarborough, who were beaten 3-0 on the tricky surface last Saturday.
If the FA agree, then the tie, scheduled to be shown live on Friday night, may be postponed or rearranged at another venue.
The Feethams turf is only about two inches deep and Scarborough complained that the grass was moving under their players' feet, and they risked injury as Darlington beat them at the weekend.
The FA are taking the matter very seriously and their own ground experts will make a thorough check of the surface this morning before delivering a verdict on whether the cup tie can go ahead as scheduled or will have to be rearranged.
Darlington had to switch their previous tie with Burnley to Middlesbrough's Riverside Stadium and now the same move could be forced on them again.