The pair, on loan from Leeds United and Liverpool respectively, have enjoyed an outstanding start to their spells at the Keepmoat Stadium - with both scheduled to remain at the club until the start of January.
But McCann, who has spoken to both parent clubs of the players about a renewal, is positive about the chances of them staying for a longer spell with Rovers, in joint third place in League One after an encouraging opening to the new season.
McCann, whose side welcome Yorkshire rivals Bradford City on Saturday, said: “We are in close contact with both (clubs). Difficult situations really, I think both Liverpool and Leeds want Herbie and Mallik to sign extensions to their contracts before they make a decision on whether they stay here for the rest of the season or go elsewhere.
“But I think they are delighted with the progress they have made. We are working hard with them every day here and they enjoy it here and want to continue it.”