The Lilywhites are still waiting for their first ever Premier League crown, but despite their strong start, Keane is unsure if Spurs can produce the goods for the whole season and become champions.
Speaking to Sky Sports News, Keane said: "[Mourinho has] done it before. His CV is fantastic. But I don't think these players he has at Spurs are good enough to win the title.
"They have the X-factor in Mourinho and Harry Kane, I don't think that's enough. They were hanging on at the end at Stamford Bridge.
"I think they are on for a very good season, but a very good season is a big difference to trying to win the league title. I don't think so. Manchester City are stronger than Spurs."
Tottenham next face a Europa League showdown with LASK Linz before Sunday's North London derby with Arsenal. body check tags ::