Daniel Flynn says Kildare let Mayo "off the hook, big time" in their second round football qualifier last weekend. Kildare led by six points early in the second half, but allowed Mayo back into the game, and the Connacht side eventually won by five.
"I was disappointed coming out of it," Flynn told BBC NI's GAA Social podcast.
"I think we let them off the hook, big time. I don't know [why that happened]. I think I had a part in it. There was a turning point where Enda Hession made a block when I got in on goal, and that would have put us six up.
"Instead, they went down, got a point; won another turnover five minutes later, got a point, and then they got the goal.
"It was on a knife edge at that stage, and we probably lost a few battles around the place. They probably had a bit more know-how. It probably never should have got to that stage."
Flynn has this season faced four of the teams remaining in the championship. Kildare defeated Dublin in the National League, and were then hammered by them in the Leinster final; they drew with Kerry in the opening game of the league; lost to Armagh by five points in the league; and lost by eight to Mayo in the final round of the league, and by five to them at the weekend.
"If I was to put money on anyone [to win the All-Ireland], it would be Kerry," said Flynn.
"I just think they are class, but Dublin could easily do it."
Asked if Mayo could "rattle" Kerry, Flynn said: "Not based on the other day. Not based on the league final. Kerry have too much firepower, man to man.
"I think they are well-drilled at the back. We played them in the first game of the league, and they had a wall of men in front of us. That's not like them."
Flynn added that he took "no umbrage" with how Jack O'Connor, the current Kerry manager, departed as Kildare boss last year.
"He'd be old school," Flynn said about O'Connor.
"Not a whole lot of video work. A big emphasis on kicking the ball, a big emphasis on supporting. He didn't complicate things. It was very simple. Attitude was a big thing. I think his first year, he was distant with his management style. The second year, he was better with the players. He had more of a bond with lads."