Sir Alex Ferguson's side grabbed the only goal of the game in the 32nd minute, but there were questions over the goalscorer, despite Darren Fletcher taking the credit from his team-mates.
Patrice Evra burst forward from left-back, provided a dangerous cross and Sol Campbell and Fletcher slid in, David James was wrong-footed and Sylvain Distin was unable to keep the ball out as he hammered it into the roof of his own net.
More pictures from the match>>> Watch Premier League goals from this weekends action. Click here.It was scant reward for a fine first-half display from the Blues, but United stepped up a gear after the break and dominated the remainder of the contest.
Although Pompey prop up the early table, they showed enough signs that they will soon be back in the points to get their season up and running.
United - along with Chelsea last weekend - will surely contest the Premier league title again this season.
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The full article contains 203 words and appears in The News newspaper.