Rovers picked up their fifth clean sheet in seven outings on Saturday with the goalless draw against Leeds United.
Defensive duo Scott Dann and Grant Hanley were impressive once more, with Appleton knowing the importance of keeping them fit.
"They've been outstanding, we've been absolutely delighted with them," the Rovers boss told Radio Rovers.
"Our concern a little bit is making sure that we get them on the field every game. The games are continuing to come thick and fast, we've obviously the game at Leicester now on Tuesday night. So it is crucial that they stay fit.
"I've said all along since I came into the football club how important clean sheets are.
"You can't lose a game and hopefully with a little bit of luck you get an opportunity to win a game as we did against Ipswich in our last fixture here.
"So as long as we keep keeping clean sheets and enjoy keeping clean sheets, hopefully someone will have a little bit of magic in the right areas and we'll get the break that we want."