Manchester City moved back to the top of the table on goal difference on Monday following their tense 1-0 victory over the Red Devils.
Sir Alex Ferguson’s side had looked set to win a 20th league crown but defeats by City and Wigan Athletic, coupled with a 4-4 draw with Everton have handed Roberto Mancini’s side the initiative with two games left to play.
“I am surprised to see United giving up an eight-point lead, but don’t forget we had a massive lead as well and lost it,” Silva told City’s website.
City captain Vincent Kompany scored the vital winner against the defending champions at the Etihad with a thunderous header on the stroke of half-time.
And Silva, who was a member of the Spain squad that won the European championship and World Cup in 2008 and 2010, believes the derby victory could turn out to be the most important win of his club career.
“We knew we had to win on Monday,” Silva added. “Mentally we were ready to win it. We did that and now we have to continue concentrating on the job.
“If we end up winning the title, Monday’s win could be the most important win of my club career. But we have to win the championship for that win to mean something.
“If we can win the Premier League, we hope it can open the door for us to win many more trophies. Last year we won the FA Cup and qualified for the Champions League.
“Beating United has given us the confidence we need for the last two games. It has been a very long and tough season. The Newcastle game is like a final for us now. We have to win it.”
The 26-year-old’s impact at City has been hampered by an ankle problem after an impressive start to the season, and the Spain international admitted his frustration at the niggling injury.
“I have been quite unlucky in the second half of the season because not only have I had constant knocks on the same ankle that has caused me a lot of trouble in the past, but just at the moment when we had a dip in form as a team,” he added.
“I’m having a lot of treatment to get movement in my ankle. It is feeling slightly better, but it helps that the team are playing better.
“All I’m thinking about is the next match on Sunday – we have to go to Newcastle and win.”
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