Wayne Rooney used to think Chelsea Football Club were impossible to beat.

Upon joining Manchester United in the summer of 2004, the England international had to sit back and watch the Blues won back-to-back Premier League titles.

This led to Rooney believing the Londoners were untouchable, but United have since bounced back to win three championships and the UEFA Champions League.

“For my first couple of seasons at United, Chelsea looked so strong,” he said. “They looked impossible to beat, really. We knew we had to back ourselves up to challenge them.”

It looks as though the two clubs will go head-to-head for the title again this season, as they both threaten to pull away from Arsenal at the business end of the campaign.

Chelsea have already beaten United this season at Stamford Bridge, and the two sides meet again at Old Trafford for the crucial return date on April 3.

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