Harry Redknapp believes that he could become the first manager in half a century to turn Tottenham Hotspur into the champions of England. Bill Nicholson achieved that feat as part of the Double in 1961 and Redknapp says "there is no reason" why the club should not end their long wait for a repeat this term.

Chelsea's vulnerability in recent weeks has given hope to the Premier League's chasing pack. The champions won their first five matches but their momentum has stalled and Redknapp believes Sunderland's 3-0 win at Stamford Bridge last week suggests that several teams, including his own, could supplant the league leaders.

"This is the most open Premier League there has ever been and anyone that can put a run together will have a great chance," said Redknapp. "I include us in that. I'm not saying we will win the title but it's not impossible – there's no reason why we can't challenge. Remember I said last season that we'd finish in the top four and we did. You've got to win these games [like Arsenal today] if you're going to look to win a championship. I think the championship is wide open this year. It's never been so open."

Redknapp believes the difference between many teams' squads is so minimal that injuries could be the decisive factor in the title race. "We saw what happened last week when Chelsea were without [Frank] Lampard, [Michael] Essien, Alex and [John] Terry," said Redknapp. "Everyone gets injuries. Whoever can get a settled side and put a couple of wins together will be right up there."

Tottenham's hopes of being that side are boosted as Jermain Defoe returns to the squad for the north London derby having recovered from the ankle ligament damage that he suffered on England duty in September.

Tottenham have been uncharacteristically profligate in front of goal this season – netting only 18 times in 13 league games – and Redknapp said they would be higher than their present seventh place if Defoe, their top scorer last season, had not been sidelined. "He would have had six or seven goals by this stage and that would have made a difference."

Keeping goals out has also been a problem for Spurs – they go to the Emirates in search of their first Premier League clean sheet since the opening day. Their fragility at the back has been caused mainly by a wretched run of injuries but Redknapp said the club's luck seems to be changing on that front: not only will Michael Dawson resume full training next week following the knee ligament damage he sustained in September, but White Hart Lane's forgotten man, Jonathan Woodgate, is progressing and pushing to make an unexpected comeback.

The 30-year-old centre-back has not played in over a year and his career seemed to be petering out as Redknapp omitted him from the 25-man squad for the first half of the league campaign and said he feared the player's persistent groin injury was "untreatable".

Now, however, Redknapp says Woodgate appears to have recovered and is about to begin a month of "intensive" training with a view to rejoining the squad for the second half of the season.

"He's worked really hard to get back," said Redknapp. "He's got to go through a pre-season, if you like, and next week he'll start a month of real intensive, hard work. If he can come through that then there's real light at the end of the tunnel for him, which would be great."

Without Woodgate, Dawson and Ledley King, the former Arsenal captain William Gallas will remain at the centre of the Tottenham defence, and will no doubt be the target of derision from many of the home fans.