Manchester United manager Alex Ferguson has called on his players to be more ruthless in order to avoid a repeat of last season's Premier League disappointment.
Ferguson saw his side pipped for the title on goal difference in May by local rivals Manchester City and during pre-season brought in Robin van Persie and Shinji Kagawa in a bid to sharpen United's cutting edge.
United have already managed 38 goals in 15 matches in all competitions -- but Ferguson felt his team almost paid the price for their wastefulness despite a dominant performance in a 2-1 win over Arsenal at Old Trafford on Saturday.
Victory in this early kick-off match took United to the top of the table and that is where they stayed after both previous leaders Chelsea and City were held to draws by Swansea and West Ham respectively later in the day.
Van Persie was on target against former club Arsenal and Patrice Evra added a second before Santi Cazorla's stoppage-time goal for the Gunners meant the full-time score failed to reflect United's dominance.
"I'm disappointed in the inability to hammer home the advantage," said Ferguson. "I spoke to them at the start of the season.
"We lost on goal difference last season and I don't want that to happen again," he added. "We had an opportunity in this game to add to our goal tally.
"Thank God we got the second because with them scoring in injury-time it would have been an embarrassment.
"With the chances we missed we should have put it to bed a long time ago," added the veteran Scottish boss, days away from the 26th anniversary of his appointment as United manager.
"You look at the scoreline and think it's a close game but it wasn't."
Van Persie continued his fine scoring form since his Â£24 million move ($39 million) from Arsenal in by scoring within three minutes of the kick-off against his old club.
Wayne Rooney missed the chance to add a second from the penalty spot but Evra doubled the lead in the second period.
Arsenal's Jack Wilshere was sent off for a second bookable offence before Cazorla scored with the final kick of the game.
Van Persie admitted United should have been more potent in attack, but added he was enjoying his flourishing partnership with Rooney.
The 29-year-old Dutchman, who refused to celebrate in front of his old supporters after putting United ahead, said: "We are both (number) nine-and-a-half.
"You have a nine and a 10 and we are a nine and a half, helping each other out and both play behind or higher up.
"It seems to work well and I'm very happy, hopefully we can keep it going."
Arsenal manager Arsene Wenger has now seen his team make their worst start to a season since he took charge of the Londoners in 1996 and this defeat left the Gunners, without a major trophy for seven years, already nine points off top spot just 10 games into the campaign.
He felt they had only themselves to blame for Saturday's loss, with defender Thomas Vermaelen's error helping van Persie open the scoring.
"We put ourselves in trouble because most of the problems we had were our mistakes when we had the ball and lost it, especially for the first goal."
The Frenchman also insisted Wilshere was unfortunate to be dismissed after receiving a second yellow card for a challenge on Evra.
"It was not deserved. He went for the ball. His game is commitment and sometimes (it happens), especially when you are tired.
"It did not look to me at all that he went over the ball on purpose."