Mauricio Pochettino is already planning to make transfers in January after Tottenham were knocked out of the Carabao Cup by Sky Bet League Two club Colchester United.
After 90 goalless minutes, the U's took another Premier League scalp, having eliminated Crystal Palace in the second round, as Tom Lapslie hit the winning spot-kick after Christian Eriksen and Lucas Moura missed in the shootout.
Pochettino, who has yet to win a trophy since taking over in 2014, spoke publicly early this season about agitation in the squad and his concerns about team spirit, with Eriksen and Jan Vertonghen among the senior players to have been left out for big matches.
Spurs produced a disjointed display that was in keeping with the start they have made to the Premier League season, and Pochettino said: "We are working so hard to put everyone on the same page.
"Only we need time. January is going to be a good opportunity too to fix this situation and the next one. That is the problem when something happens that you cannot control.
"It means we are human and in football to keep the successful period in football you need to be different every season and find different solutions. We need to do something different and we will do that.
"We lost the game by penalties and today was about winning. When you play at this stage, it's not about the performance but the result.
"That's the beauty of the competition, always something can happen. We wanted to go further but we are out.
"When you have an unsettled squad always it's difficult and you lose time and then you need time to recover the time you lose. That's where we are.
Tottenham's shock exit in stats
Colchester become the first team from outside the top flight to win a penalty shootout against two Premier League sides in a League Cup campaign since Bradford did so en route to the final in 2013.
Tottenham meanwhile have been eliminated by a side from a lower division in the League Cup for the first time since 2005-06 against Grimsby.
"Maybe our performances are good but you need this extra, which is mental, connection, it's energy to be all together, not to have different agendas in the squad.
"We need time again to build that togetherness that you need when you are competing at this level."
Analysis: Tottenham must start winning silverware
Tottenham must start winning trophies in order to be viewed as making progress under Pochettino, according to former head coach Tim Sherwood.
"I can't believe it - Colchester are the lowest-ranked team left in the competition," Sherwood told The Debate. "They just couldn't get anything going and didn't create too many clear-cut chances.
"I'm all for going for this competition when you haven't won anything for such a long period of time, and I just think it's an opportunity missed to get to the next stage.
"They should've just got the job done and brought the big players off after. Having said that, the starting line-up should've been good enough to beat a League Two team anyway.
"I thought it would be only a matter of time even without the big guns, but then I saw Son and Eriksen coming on, and then Erik Lamela, and I thought they would open them up but they got into a rut and it was very stale. They got very safe and there was no one taking any risks.
"I know those fans want to win a trophy, and of course Mauricio would want to win one as well. It's all about winning something for these guys now, and we've said it many times."
Despite making 10 changes to the side that were beaten 2-1 by Leicester at the King Power Stadium, there was still enough quality in the Tottenham side to avoid an upset.
Sherwood added: "Mauricio has every right to look at the players who started tonight and ask them, 'are you really pushing to play in my team in the Premier League? Are you really pushing if we get to the Champions League this year?
"Were you willing to be brave on the ball at Colchester? There's no consistency. Last week, they beat Crystal Palace in half an hour, and then they lost at Leicester. You never know what you're going to get.
"He is looking for consistency, but you only get that through a consistent team. He's perhaps rotating too much at the moment. On the face of it, he knows that three players will be leaving - Eriksen, Toby Alderweireld and Vertonghen will be leaving for nothing which will hurt the club.
"If they want to move to a bigger club than Tottenham, they have to perform well."