Diarmuid Connolly believes Dublin must make a case for the defence if they are to retain their All-Ireland crown.
The five-in-a-row champions begin their Championship quest again tomorrow (6.15pm) against Westmeath but there has been no shortage of upheaval on and off the pitch.
Connolly himself has announced his retirement while Bernard Brogan, Eoghan O'Gara, Darren Daly and manager Jim Gavin also called it a day at the top level.
Dublin were further set back by Jack McCaffrey's surprise decision to step away from inter-county football, while Paul Clarke left the back room team under new boss Dessie Farrell.
Key defender Jonny Cooper limped off in a recent League game but the Dubs have Rory O'Carroll back on board this season.
Connolly told Boylesports: “My big question mark for Dublin this year will be in the full-back line. Are they going to have a consistent full-back line? Because usually when we do, we can shore up the back and the lads up front will always get the scores.
“Dublin have a few guys who can be a huge influence on the Championship and most of them are in the forward line," said the six-time All-Ireland winner.
After such a transitional and extraordinary 12 months, Connolly also expects to see a fresh look about Farrell's Dublin team.
"I think Cormac Costello will have a big influence and the competition for places is phenomenal at the minute in the forward line," he said.
“We saw the impact Sean Bugler had off the bench the last day and he’s a phenomenal talent. Paddy Small is exactly the same, he was one of the leaders actually the last day and he’s been immense throughout the Dublin Championship. He can draw two or three men to him and create space for other people.
"They may be a little bit of an unknown when it comes to the inter-county scene, but I’ve seen these guys for years and they are well able to mix it.”
