Brennan’s return to the sideline following a 12-week ban came in the win against Cavan following a round one defeat by Louth and Dublin have improved game by game.
That ban, along with Donegal manager Jim McGuinness escaping a similar punishment for his part in a fracas against Kerry, may have instilled a “siege mentality” according to Beggan, but some below-par displays earlier this year may have also galvanised the group.
“Having him back along the line is the extra boost, but we can’t forget Dublin scraped over the line against Wicklow in a Leinster quarter-final,” he continued.
“Maybe those were the type of games have helped bring them on as they may think ‘we’re not as good as we think we are, so we have to knuckle down here’ and I can imagine Ger was in the background saying something similar.
“It wouldn’t surprise me if they were to get a result this weekend. I still think it’s a Kerry win but you just don’t know with this championship.”
Kerry have also been building throughout the championship as after their defeat by Donegal in round one, they ruthlessly put Kildare and Armagh to the sword.
It as a lot tighter in the quarter-final against Tyrone, but that could well be a “blessing in disguise”, according to Beggan.
“Maybe some are starting to think Kerry can be got at, but like Dublin, they’ve players coming back in and three massive games that will have brought Joe O’Connor and Gavin White on and that will be a serious help to get them over these next few weeks.
“Kerry are still clear favourites but the game against Tyrone will keep the mind focused.”