Ciaran Whelan believes Dublin and Kerry's Allianz Football League clash at Croke Park highlighted the significant effect the new black card rule will have going forward.

Players are sent to the sin bin for ten minutes after referees show them a black card and both Dublin and Kerry had players punished during an absorbing contest.

Speaking on RTÉ2's Saturday GAA Live after the match, RTÉ GAA analyst Whelan touched on the effect of the black card, especially in the closing stages when Kerry's momentary man advantage following Eric Lowndes' red card disappeared as Graham O'Sullivan was sin-binned in the final stages.

"What we did see really was the impact of the black card," said the former Dublin footballer.

"Kerry, three-point lead and a man up, then they get a black card.

"It's back to 14-all and Dublin, as Dublin do in that last ten minutes, push forward and run at Kerry and create opportunities to get back into the game.

"And I think the black card is going to be very, very interesting."

One major concern about the regulation around the sin bin has been the fact that the clock is not stopped during the ten minutes in which a player is sidelined.

That opens up the possibility for teams to waste time while they are down a player. 

Nevertheless, Whelan feels the black card will still have an overwhelming impact.

"As much as people will use it, bend the rules to try and slow the game down, it does have a significant impact on teams," he continued.   

"It's going to add that bit of excitement and if you get a team that gets a second black card in that ten minute period, it's going to have a huge impact.

"We definitely learned stuff tonight. It was very slow, lots of cards, scrappy second half and maybe that's to do with January.

"The energy maybe wasn't in the legs for the last 15 to 20 minutes."

Whelan believes Dublin manager Dessie Farrell will be more content with the 1-19 to 1-19 draw compared to his Kerry counterpart Peter Keane.

"From a Kerry perspective, I think Kerry will be disappointed that they just didn't get out of here with a tight win," he said.

"Because I think they possibly might have needed it more than Dublin. But Dessie Farrell will also be happy."