From 2015-21, Dublin were unbeaten in 26 knockout Championship games, until Mayo finally ended their run in the All-Ireland semi-final two years ago.
They’ve now lost two of their last three, last year’s quarter-final win over Cork the exception before Kerry edged them out in the subsequent semi-final.
And with Mayo their opponents again this Sunday, Dublin face arguably their most difficult assignment in a quarter-final since the watershed beating they shipped from Kerry in 2009.
Having fallen the right side of so many close-run encounters at the back end of the Championship as they subsequently won eight All-Irelands, Cormac Costello is asked to identify where Dublin have been lacking over the past couple of years.
“Any game that you lose that close, you are going to zoom in on everything that went wrong,” said the Dublin forward.
“If you come out the right side of it, like we have many times, it sort of papers over the cracks.
“But last year our performance wasn’t good enough in the first half against Kerry and overall they were the better team. You would look at some of our chances and our efficiency wasn’t great, so they are the main things you would go after.”
Another theory could be that they missed the leadership of the most successful captain in GAA history, with Stephen Cluxton in exile for each of the last two campaigns before making a dramatic return to the panel ahead of the final round League game against Louth earlier this year.
As such, Cluxton’s unbeaten record stretches back to 2014.
“It was a surprise but there was chat going on in the background,” Costello explained. “He came in in the week of the Louth game. He was just like Clucko. He’s such a professional. It was like he never left.
“He just carries himself really well. We welcomed him back with open arms. But the door was always open.
“He’s obviously a professional but the way you see some people playing on the pitch mightn’t be how they are off the pitch. No, he’s a lot more approachable than people might think he is.
“Look at his career to date. He’s someone who is always trying to be his best. Whether that’s in a skill session in training or a heavy session, he’s always putting on his boots and going in with the same mindset.
“That mindset can only rub off on you and be a positive impact on the dressing room.”
Having remained on the bench for the opening Championship game against Laois, Cluxton was back in the starting line-up for the Leinster semi-final against Kildare and has stayed there since.
Na Fianna’s David O’Hanlon had probably exceeded expectations with his performances up to then but he’s now been relegated to third choice since Evan Comerford’s return from injury.
“Dave O’Hanlon had a great League campaign, arguably our best player in the League. Evan was magnificent the last two years with Stephen gone.
“But it’s like anything, there’s competition in all places in the team. Everyone is just trying to do the best and try and get into the team.”
There is a sense that, with knockout football finally having kicked in, Dublin will now raise their game accordingly but Costello insists that they’ve been fully tuned in since January.
“We’ve taken it serious since day dot. Because we had to regain Division One status, we knew how important that would be. We struggled through some games in the Leinster campaign.
“We had a good performance in the Leinster final. We struggled against Kildare. But like I said, it’s do or die. The safety net is gone. There’s no second chances now.
“I don’t think anyone is looking at it thinking we’re going to hit the ground running at this time of year. It just probably adds to a bit more of tension because the safety net is gone.
“And then the noise outside the camp and people talking about do or die.”
There has been much grumbling about how so many games of questionable importance have been rolled out before finally arriving at the business end of the season and, though Costello missed the last two round robin games with injury, he’s a fan of the new-look Championship.
“Personally, I liked it. What do I do? I love playing Gaelic football. I love playing matches. Less training you have to do.
“But playing games is great. It really came to life with the different permutations at different stages of the day (in the last round of group games).”
Between League and Championship, Mayo have played 11 games against Division One opposition this year compared to just one for Dublin, who laboured for long periods before drawing with Roscommon in the group stage opener last month.
“We don’t really know where we’re at,” Costello admitted. “We’ve only played one Division One team this year and we struggled.
“So to get a true representation of where we’re at… we don’t know. All we can do is focus on ourselves and try and go in with our best foot forward.”
Costello has enjoyed his best run as a starting player for Dublin in recent seasons, though he jokes that the privilege may be under threat when his father, John, retires as county secretary later this year.
“I’ll be gone! I’m under pressure, I’ll have to put in a word with whoever goes in next. I think he’s finishing up in October.”
Having been in the role since 1994, overseeing a period of unprecedented success, Costello acknowledges that his father will miss the involvement.
“I’d say he will, definitely. He’s been at it for so long, but I’m sure he’ll keep himself busy somehow, ma won’t let him hang around the house anyway.”
