Mauricio Pochettino insists he needs time to implement his methods at Tottenham but admits results must improve after Spurs slipped to a 2-1 defeat at home to Stoke yesterday.
Stoke were two ahead before the break thanks to strikes from Bojan Krkic and Jonathan Walters and the Potters held off a late rally after Nacer Chadli had given the hosts hope late on.
Spurs have now lost four out of their last five home games in the league and the latest defeat sees Pochettino's men drop to 12th in the Premier League table.
"It's clear from the results that we need to improve, we need to improve a lot," Pochettino said. "It's another defeat and we need to improve, this is clear to see.
"In football you always need time to implement different methods but we need to improve quickly because you never have a long time in football.
"You need to get results and we need to find a solution quickly. My challenge in the next few weeks is to change the mentality and to find that solution."
Stoke jump above Spurs into ninth in the table after recording their first win in four matches.
Mark Hughes admits his team sensed their opponents' lack of confidence and was delighted with how the Potters took advantage.
"Maybe there's a little bit of pressure on the Tottenham players at the moment and we sensed if we started quickly we could use that to our own ends," Hughes said.
"Spurs are a good team, individually they have some great talent, but we got our shape and structure right and understood what it takes to take a positive result away from home - which we've struggled with."