Arsene Wenger realises Arsenal will not win any silverware if they throw away winning positions. The Gunners looked on course to go top of the Barclays Premier League after they romped into a 2-0 half-time lead over north London rivals Tottenham at Emirates Stadium on Saturday.
But Spurs rallied to produce a remarkable fightback to win 3-2 and record their first away win over their old enemy since 1993.
And Wenger accepts there cannot be any more careless displays if his young side are to finally come of age in 2011.
"It is painful, but more because we had an opportunity to go top of the league that we did not take, and a mature team, you want them to do it," said Wenger, with Arsenal now down to third place, two points behind Manchester United who are behind Chelsea only on goal difference.
"That is what hurts the most, because that is what is needed if you want to be successful and win trophies."
Wenger continued: "We delivered quite a good game and created many chances.
"What is much more difficult to understand is that we lack some basic concentration on facts in the game where you can be punished. When you want to win, that cannot happen."
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