Sheffield United manager Chris Wilder was left frustrated with his side's defending as they threw away a lead to lose at home to leaders Coventry.
Harrison Burrows drove the Blades ahead but Coventry rallied to score twice in five minutes through Haji Wright and Jack Rudoni to leave United nine points short of the play-off places.
Wilder told BBC Radio Sheffield: "It was a really good performance for large parts but the naivety for the two goals was incredible. We should be up at half-time, the tone and feel of the stadium was really good and we had them on the back foot.
"We went toe-to-toe and got ahead but the manner of the goals we conceded was so naive. We were wide open for the first and then we turn our back on the second one. The game turned on its head.
"We had to be smart and manage the game and we didn't do that. I feel for the players, but it's just happened too many times this season. We have nearly been good enough."
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