Ange Postecoglou has said the last thing he wanted at Tottenham was a lack of harmony as he addressed the anti-Daniel Levy chants from a section of the fanbase and battled to turn around the club’s Premier League fortunes.

Spurs go to Brentford on Sunday having taken five points from their past 11 matches, a run that has dropped them to 15th and led some supporters to call for the departure of Levy, the chairman of 24 years’ standing.

Postecoglou is not in the business of telling fans what they should say or do. Perhaps the manager has been burned by what happened at the end of last season when he took issue with how many of them wanted Spurs to lose against Manchester City rather than win and help Arsenal towards the title.

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However, as Postecoglou again admitted, he had failed to bring unity to Spurs given the continuing enmity towards Levy and it is clear he would prefer not to have such a sideshow. Much better would be the type of support his young team heard on Thursday night in the home win over Elfsborg in the Europa League, although there were still choruses of “Levy out”.

“I’ve always felt when you are trying to build something successful, you need to be united,” Postecoglou said. “I have probably failed in trying to unify the club. Part of that is just because of the form we are in in the league, which allows people’s minds to go away from the here and now.

“I thought the crowd were good [against Elfsborg]. They understood we had a young squad out there and they got genuinely excited towards the end of the game seeing the young boys. That’s what we’re trying to tap into because we’re going to need the support in this last phase of the season to hopefully create something special.

“I have often said I can’t sit here and dictate to people what they should or shouldn’t do. My role is to try and create an environment where we are unified and we have to be unified. Particularly when you go through tough times, the last thing you want is splintering in our mindset and focus.”

Postecoglou was asked whether he felt unity at the club was impossible given the dynamics between Levy and some fans, or if he was hopeful of it still becoming a reality. “It’s not that it can’t happen, it just makes it more difficult,” the manager said. “It’s not an unusual situation for me – I’ve faced it before at other clubs. Usually when you get things right on the field that gets everyone aligned again. All I can do is my utmost to get the team back on track in the league and give our supporters the priority of just enjoying our football team.”

What Postecoglou wants from Levy before the closure of the transfer window on Monday night is a signing or two. He has been calling for action in the market for weeks and it was no different on Friday. Postecoglou needs a player for the front line and the club have indicated a readiness to pay €60m (£50m) for Bayern Munich’s Mathys Tel. The forward, though, has other offers and is not inclined to join Spurs.

Postecoglou also said the club may have to look for a new centre-half given the uncertainty over Cristian Romero and Radu Dragusin. Romero has been out since early December with a thigh injury and Postecoglou said the situation was “tricky,” with no comeback date for the Argentina international. “It’s just a slower healer with him and it is one we are looking at on a week-to-week basis,” he said. Dragusin went off with a knee problem against Elfsborg and while there is no clarity on its severity, the concern is obvious.

The Australian will be without nine injured players at Brentford but he reported that six of them – Guglielmo Vicario, Destiny Udogie, James Maddison, Brennan Johnson, Wilson Odobert and Timo Werner – should return to training in the week leading up to the visit of Manchester United on 16 February. Dominic Solanke is expected to be out until late February.

Postecoglou talked about the United game as being “a point for us to relaunch our campaign”. As things stand, none of the injured players are likely to be available for Thursday’s Carabao Cup semi-final second leg at Liverpool or for the FA Cup fourth round tie at Aston Villa three days later. He hoped the situation was about to improve but added: “Every time I’ve seen the light at the end of the tunnel it’s usually been an oncoming train. We seem to be losing players as we get them back.”