London: Wayne Rooney and Robin van Persie will need to deliver when the team heads to Newcastle for the Premier League's standout game this weekend.
United have fallen behind in six of their nine games this season, including last weekend when Tottenham raced into an early lead and hung on for a 3-2 win that ended a 23-year barren run at Old Trafford.
That result saw United slip to third place - four points behind early leader Chelsea after six games - and a defense lacking captain Nemanja Vidic is sure to come under more scrutiny at St James' Park on Sunday (2am AEDT Monday), with Newcastle having the top scorer in the league in Demba Ba.
"It does bother us having to come from behind because we are losing those early goals," Rooney said.
"It is not nice and it is something that we have to stop because we cannot afford to keep letting teams get a head start on us."
Thankfully for United, the team has Van Persie in great scoring form in attack, with seven goals in eight games since his move from Arsenal, and Rooney fully recovered from a badly gashed leg that kept him out for a month.
The pair started together for the first time in this week's match against Cluj, with Rooney - playing in an attacking midfield role - setting up both of Van Persie's goals in a 2-1 win in Romania.
"The best quality both of them have is that they can turn a game," United manager Alex Ferguson said. "That is an important feature. It doesn't really matter if they have a personal combination, it is their ability to finish moves off, whether it is through (Tom) Cleverley, Nani or (Antonio) Valencia.
"We have a pair of really top players who can finish and change a game."
Mid-table Newcastle beat United 3-0 in the corresponding fixture last season, helped by a commanding display by Ba, who has started this season with a goal-a-game average.
Ba and his fellow Senegal striker Papiss Demba Cisse will fancy their chances of ruffling a United defense that is shorn of injured trio Phil Jones, Chris Smalling and Vidic. With another centre back, Jonny Evans, limping off against Cluj, Ferguson is so short of cover in his backline that youngster Scott Wootton could be called up to start alongside Rio Ferdinand.
By the time United play, they could be seven points behind Chelsea in the standings with the European champions hosting Norwich on Saturday at midnight AEST. Second-place Everton, who are a point ahead of United, are at Wigan, fourth-place Manchester City play Sunderland and Arsenal are at West Ham.
Chelsea, who along with City and Sunderland is unbeaten after seven weeks of the campaign, have won all three league games at Stamford Bridge and has added creativity up front to its trademark steel in defense to set a fierce pace at the top.
Such is the form of the team that manager Roberto di Matteo's decision to leave out experienced midfield stalwart Frank Lampard for some recent games has largely gone unnoticed.
Instead, Chelsea fans have been revelling in the performances of attacking midfielders Eden Hazard, Oscar and Juan Mata, who could have a field day against a Norwich defense that conceded five against a previously struggling Liverpool last weekend.
Like United, Man City will need to rectify problems in defense if they are to keep pace with Chelsea.
Manager Roberto Mancini hasn't settled on his best backline this season and his team is yet to keep a clean sheet, despite some fine displays by goalkeeper Joe Hart - the latest coming in the 1-1 draw at home to Borussia Dortmund in the Champions League on Wednesday.
"This is my problem, is my job. I will solve this problem," Mancini vowed.
Traditionally a slow starter to league campaigns, Everton have won four of their six matches ahead of a trip to Wigan, who have lost their last three league games.
"Right now the mood is really good," Everton goalkeeper Tim Howard said. "In order for us to do great things, we have to punch above our weight.
"We are not a huge squad, and we don't have boatloads of money like other clubs, so in order for us to get the job done we have to stay really consistent for quite a few months."
On Saturday, it's also: Swansea vs Reading and West Bromwich Albion v last-place Queens Park Rangers.
On Sunday, Liverpool host Stoke, Tottenham are at home to Aston Villa and Fulham travel to Southampton.