With United having beaten Sunderland 1-0 and City drawing 2-2 with Queens Park Rangers, the title seemed destined to return to Old Trafford for another year.
But Sergio Aguero’s last-gasp winner secured the Eastlands outfit’s first top-flight crown since 1968 and meant United ended the season trophy-less.
“Sunday was a difficult day for everyone,” said Rooney. “One minute you think we have won the title, then we haven’t, which was heartbreaking.
“That is how it goes sometimes. We have to believe in ourselves. We have to look forward to next season and hopefully we can win some trophies next season. I am sure we will be back. We all believe in ourselves.”
United eventually lost the title on goal difference – and Rooney pointed to the Red Devils’ 4-4 draw with Everton as the turning point in the season, after Sir Alex Ferguson’s men looked on course for three points against the Merseysiders.
Rooney continued: “The biggest disappointment was the Everton game. To be 4-2 up — with 10 minutes to go — and to lose that lead is hugely disappointing.
“But there are a lot of young players in the team. That is only going to benefit them. They will learn from that.”
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