Ange Postecoglou has backed Tottenham’s players to move on quickly from Harry Kane’s departure on the eve of the Premier League season as the England captain prepared to complete his transfer to Bayern Munich and end a 19-year association with Spurs.

Kane flew to Germany on Friday evening and was expected to undergo his medical after Tottenham accepted a bid that could be worth almost £100m. The deal was briefly held up on Friday by the Tottenham chairman, Daniel Levy, renegotiating elements of the fee at a late stage but Postecoglou confirmed the move was “imminent” and that he had been preparing his squad to face Brentford on Sundaytomorrow without Kane.

“He sent me a message and I sent him a message back,” the manager said when asked whether he had spoken to Kane since the offer had been accepted. “I don’t think either of us were surprised by the outcome.

“We’d been talking about it all along anyway, whether that’s about his situation or the club. I found out fairly early in my career that football clubs move on pretty quickly. I think we dwell on things when the players know there is no time to. After 48 hours they have their first Premier League game – that is where their focus is.”

It is unlikely Kane will be registered in time to play against RB Leipzig in the Super Cup on Saturday night but Bayern are hopeful of unveiling him to supporters before the match in Munich. Postecoglou admitted he had been prepared for the 30-year-old’s departure since taking over after leaving Celtic in June.

“It wasn’t part of the contract negotiations that I needed certain players to stay,” he said. “You do due diligence when you take a job and hopefully I was well-researched enough to know what was going on in the background. You have these conversations with people and it was in the public arena. When a player of Harry’s stature is going into the last year of his contract you don’t need too much investigative research to know what’s going on. I knew going into it that this was the most likely outcome.”

Spurs do not intend to spend the whole Kane fee on a striker. Postecoglou is prepared to give Richarlison, who had a disappointing first season at the club, an opportunity in a central role and would like to bring in versatile players who can play across the front three. Brennan Johnson, the Nottingham Forest winger, is a target.

Postecoglou and Tuchel confirm Harry Kane is close to joining Bayern – video

Tottenham offered Kane a new contract that would have doubled his £200,000-a-week terms and Levy turned down several bids from Bayern before accepting a fee that smashes the Bundesliga club’s €80m transfer record. Bayern are understood to have matched the £400,000-a-week wages offered by Spurs.

Postecoglou revealed Kane had yet to say his goodbyes to the rest of the squad but is hopeful other players can fill the void left by the club’s record goalscorer.

“All you can do is create that space and see what grows from there,” he said. “With all these things there’s opportunity. What you’ve got to try to do is what the great clubs do, the great organisations: replace greatness with greatness. How that comes about is not easy – but that’s what the big clubs do. They find a way to sustain and maintain and grow even when the greatest leave their doors.

“I didn’t wake up this morning trying to cultivate that – that’s been happening all along. I guess the finality of it all today kind of hits everyone and everyone is going: ‘What next? What next?’ But this is not new for me. This is five or six weeks of knowing it was going to happen so we have been contemplating that anyway in the way that we have been going about things. So nothing really changes there.”

Kane has won the Premier League Golden Boot three times and his 213 goals in 320 league games for Spurs mean he is only 47 behind Alan Shearer’s Premier League record. Postecoglou insisted Kane’s spell at the club should be remembered for those feats and not be defined by the fact that he could not inspire them to end a trophy drought that stretches back to 2008.

“That’s doing a great disservice to a guy who did some unbelievable things,” he said. “There wouldn’t be a manager in the Premier League or the world that wouldn’t want Harry Kane in their team. That’s the reality of it. So you can’t say that because he’s here that’s sort of stymied the club into [not] having success; I just don’t buy into that.

“I just think he’s done his utmost to try to have success at this football club and it hasn’t worked for him for a number of reasons. What we do know about this game, it’s very, very, very rare that an individual will be the difference. It’s usually the collective, so what that offers now is an opportunity to build a collective that brings us success.”