Two of this year's biggest titles have seen a huge decline in opening week sales compared to previous releases, MCV has revealed.

The site reports that sales of Assassin's Creed 4: Black Flag were down 60 per cent on last year's Assassin's Creed 3, with sales of Battlefield 4 falling 69 per cent compared to 2011's Battlefield 3.

It also states that first week sales of FIFA 14 were down 24 per cent over last year's FIFA 13.

Sales of Call of Duty: Ghosts are also expected to have fallen over 2012's Call of Duty: Black Ops 2.

Though the fall in sales is partly to be expected given the imminent arrival of next-gen consoles, there's still uncertainty over whether sales will meet those of previous releases even when the consoles finally arrive.

"We've never had two must-have consoles launched so close together," Dorian Bloch, director at GfK Chart-Track told MCV. "The unquantifiable question is, how many consumers are waiting on these franchises for a few more weeks?

"How many PS4s and Xbox Ones will have sold by Christmas? I would say, let the dust settle on 2013 and then we will know more."

Assassin's Creed 4: Black Flag entered this week's chart at No.1 with Battlefield 4 following in second place. Call of Duty: Ghosts is expected to take the top spot next week.

Xbox One is the first next-gen console to arrive in the UK, launching on November 22, with PlayStation 4 following one week later on November 29.