The experienced defender is set to wear the captain's armband against his former club in an eagerly-awaited Premier League derby at the Lane, kick-off 12.45pm.
Chelsea top the table with six wins in seven but we're hot on the heels of the top group in fifth with four league wins on the trot.
One of those victoties was at Old Trafford - and William feels the football world will be watching to see if we can produce a repeat performance.
"I am looking forward to the game, everyone here is, it is a pleasure to play in a game like this,” he said.
“These derbies are very important for the fans, the players and the Club and I’m sure the atmosphere will be electric.
“But we are not here for revenge. Last season, we tried our best to qualify for the Champions League and we were unlucky in the end because Chelsea won the competition and took our place, but we are not talking about that.
“This is a Premier League game, three points are at stake for both teams and it only affects this season, nothing else.
"Of course it is an important game for us, people will be watching to see if we can beat Chelsea after winning at Old Trafford, or whether that win against United was just luck. We have to prove how good we are."
This is an extract from William's exclusive interview over seven pages in tomorrow's official matchday programme - on-sale tomorrow at White Hart Lane, 100 pages, £3.50.
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