Ronnie Moore conceded his Tranmere side simply did not hit top gear against Brentford as they were held to a 1-1 draw.
Unbeaten Rovers looked set to clinch another home win after Jean-Louis Akpa Akpro put them ahead just before the hour mark.
But Jonathan Douglas took advantage of some slack home defending in the fifth minute of added time to volley home.
"It was a tough game and we never really got going in the first half," Moore said. "After the break we upped the tempo and I thought there was only one side who were going to win it because I couldn't see how Brentford would score.
"But to concede the way we did was very sloppy. We stepped back and let it bounce and it ended up in our net so it was disappointing to see how the goal went in.
"Overall it was probably a fair result but we are greedy and we wanted all three points. In the dressing room the atmosphere feels like a defeat but if we take stock we will realise that we are three points clear at the top."