Swindon boss Paolo Di Canio called on his charges to "become a nasty team, a malicious team" after they clung on for a 2-1 victory over Portsmouth at Fratton Park.
The Robins dominated the south cast outfit for the first 80 minutes, playing free-flowing football and taking charge through goals from Matt Ritchie after 45 minutes and Andy Williams after 55 minutes.
But cash-strapped Pompey fought back furiously in the final 10 minutes. Debutant Lubomir Michalik headed a goal two minutes into stoppage time as the hosts laid siege to the Robins goal.
Di Canio's side has been tipped for promotion, but the Italian says Swindon must learn to close games out before they can mix it at the npower League One summit.
He said: "I learnt that we are not ready yet for the top of the league. This is a different level. If you switch off for eight minutes, you can concede five goals to the opponent.
"We played 80 minutes where we should have been 10 or 12 goals up. We didn't take all the chances; it's not possible every time. But we then switched off a bit and the opponent created four or five clear chances.
"We have to grow up like we did last year and realise we have to work, analyse the last 10 minutes and become a nasty team, a malicious team in every situation."
Portsmouth manager Michael Appleton feels his men deserved something from the game and was pleased with their grandstand finish. He said: "I'm a bit frustrated we haven't come away with anything. I thought we were well worth a point at least.
"They had a lot of opportunities from set-pieces and corners in the first half. They kept us penned in a little bit. But I always felt we could score goals the way we were playing.
"I think the spirit they showed in the second half fills me with confidence that there is still a lot of belief in the dressing room and a lot of character."