Goals from Winston Reid, Ricardo Vaz Te and Ravel Morrison stunned Tottenham on Sunday, but the defender feels it is too early to be judging the squad.
Heading into the weekend clash, the visitors were yet to score a goal away from home while Spurs had not conceded in front of their own fans - but Winston Reid, Ricardo Vaz Te and Ravel Morrison saw the hosts lose pace with their top-of-the-table rival.
While Walker has been impressed with Andre Villas-Boas' summer business - spending upwards of 100 million pounds - and the level at which the new recruits have adapted themselves into the squad, he feels there is still more to come.
"It’s a bit too early to be talking about where we can be at the end," Walker is quoted as saying by the Daily Mirror. "But if we keep playing to our strengths, then I see no reason why we cannot make the top four.
"We’ve made a lot of changes to the squad during the summer, but everyone who has come in has fitted in really well within the dressing room, all the lads get along and that really helps. We’ve signed quality throughout the squad and the more we get used to playing as a team, the better we are going to get."
Tottenham currently sits sixth in the Premier League standings, with a tally of 13 points from its opening seven games.