Pressing is a vital feature of Postecoglou and Klopp's teams, with both managers enforcing a high-octane brand of attacking football.

Postecoglou and Klopp were also coming off drought-ending title triumphs as the coronavirus pandemic set in.

In 2019, F.Marinos boss Postecoglou guided the Japanese club to their first J.League title since 2004, while Klopp ended Liverpool's 30-year league drought in the Premier League last season.

But F.Marinos were unable to back it up, finishing ninth and 36 points adrift of champions Kawasaki Frontale last year. Klopp has already publicly conceded Liverpool's title defence is over – the Reds are sixth and 19 points behind runaway leader Manchester City with 13 matches remaining in 2020-2021.

The struggles are no coincidence amid demanding schedules and mounting injury lists as a result of COVID-19.

"Absolutely," Postecoglou told Stats Perform News when asked if he could relate to Klopp as he prepares for Friday's season opener against Kawasaki. "Not so much on the success bit, but you look at their football, it's high intensity and it's just not sustainable when you have such a congested fixture list.

"It's not just them. Any team around the world who play that play that high intensity, particularly with the pressing aspect not so much in possession, have found it very difficult. Liverpool are a classic example of that. Even like a club like Southampton, who pride themselves on that pressing aspect have struggled this season.

"The way you struggle, it's not just about the results, but you lose players to injuries, trying to maintain that kind of intensity. Rotation of players affects the fluency of how you play. What I found last year especially, you can kind of rotate the front half of your team and still sort of get some stability and consistency in results but if you have to change centre-backs and defenders regularly, you're going to struggle. That's definitely where we struggled last year. I don't think there was more than half-a-dozen games where we had the same centre-back pairing and goalkeeper in a row because of the injuries we had. We conceded a lot of goals.

"You look at Liverpool and most of their injury problems have been at the back. The converse of that, I look at Kawasaki who were so dominant in our league. They were really stable in terms of their back four and didn't really make changes. Had more depth in the front third where they could rotate players. Their game was based around keeping the ball, they weren’t as aggressive in the process. I think data wise they were the lowest-running team in the league. That was definitely the way to go last year. They had the quality to do it also, it's not an easy way to play.

"Even reading about Pep Guardiola's comments that his trying to get his team to run less through this period and they've been more effective. There's definitely a correlation there with the amount of running you need to do to play your style of game. The more it is, the more effective it is during this period."

Having changed the landscape of Australian football following back-to-back A-League titles and a record 36-match unbeaten streak at Brisbane Roar, plus a ground-breaking 2015 Asian Cup triumph with the Socceroos, Postecoglou took Japan and Asia by storm in 2019.

Cut from the same cloth as Guardiola and Maurizio Sarri – an emphasis on attacking football, with an unrelenting belief in their philosophy – Postecoglou's F.Marinos dazzled their way to J.League glory in 2019, ahead of FC Tokyo.

However, F.Marinos – who are part of the City Football Group – were unable to go back-to-back after, as Postecoglou says, the J.League "congested a season into really five months" while the club also juggled Asian Champions League commitments.

F.Marinos made a red-hot start to the season before the 2020 campaign was initially suspended due to coronavirus. Their title defence quickly turned pear-shaped.

While their attacking and possession numbers were around the same mark from 2019 to 2020 – only champions Kawasaki scored more goals – the same could not be said in terms of F.Marinos' defence.

F.Marinos conceded 59 goals last season, having only shipped 38 as they ended their 15-year wait for J.League silverware. Outside the box, 11 goals were conceded – up from three the year prior, while they allowed 47 shots from outside the box (21 in 2019).

There were also big differences in saves to shots ratio (69.1 per cent to 61.9 per cent), saves to shots ratio inside box (65.6 per cent to 55.0 per cent) and saves to shots ratio outside box (85.7 per cent to 76.6 per cent).

"We all had to deal with something that was unique," Postecoglou said when discussing the impact of COVID-19 on football. "None of us in our lifetime had gone through something like that or remotely like that. At the beginning, it was kind of surreal because you thought it would pass but then it kept being part of almost your existence where you have these restrictions placed upon you. To be fair here in Japan, they dealt with it pretty well. We didn't really have any major lockdown. Life, for the most part, was fairly normal. It definitely affected our football season.

"It took a heavy toll on players and staff, not just us but all clubs. We had the added challenge of being in the ACL [Asian Champions League], which affected our schedule even further. Playing without fans and empty stadiums, there was a surreal feeling about. The predominant feeling was lets just get through it the best way we can and make the most of it. We were still able to do what we love, work in a normal sense."

The absence of fans due to the coronavirus crisis also cannot be understated. While a limited amount of supporters returned for J.League matches at the backend of the 2020 season after fixtures were initially staged behind closed doors, Postecoglou said: "It actually affects football games. Supporters, they don't just provide the theatre and atmosphere, they have an effect on the players and coaches.

"Anyone who knows and has played in a stadium away from home with a passionate support, it can be intimidating, it can affect your game. If you're chasing the game, having the support in the stadium can lift you or make your opposition nervous. It definitely affects. In the beginning, it felt like every game was a friendly game – it had that sort of lack of cutting edge and little bit of intensity that you feel in real games. Eventually, I think players and coaches got used to it and games sort of turned back to a normal mode."

While 2020 did not go according to plan, Postecoglou is not dwelling on the past season.

"It was such an outlier of a season," the former Australia boss added. "Are those kind of circumstances ever going to happen again? If they ever do, there is certain things you'd probably do differently – the way we trained and played games. If you try to make a major shift from what happened last year, even though this year is looking like a very affected year for all of us, we kind of expect things to get back to some kind of normal in the near future.

"If you just react to what happened last year and change in any meaningful way what you do, I'm not entirely convinced that's a good sample to sort of say we can do things better purely focusing on what happened last year. In a footballing sense, if we are in that situation of playing so many games, we probably would've played differently and tried to play with less intensity because having so many games made it difficult for our players."

Postecoglou, like Manchester City manager Guardiola and ex-Chelsea and Juventus boss Sarri, pushes the boundaries. His approach never waivers and success follows the highly rated 55-year-old in his pursuit of excellence.

All eyes will be once again on his free-flowing F.Marinos team, with Postecoglou steadfast in his beliefs as he attempts to establish the historic Yokohama-based club – the longest-serving team in the Japanese top flight along with Kashima Antlers, having played in the J.League every year since its inception in 1992 – among Japan's elite.

"To me, it's just about 'can we play our football?' To be fair, we did even last year. It's a super competitive league. We had some fantastic success, but we aren't one of the big clubs yet. For us to be a big club, we need to have a certain level of performance year in, year out," said Postecoglou.

"Last year I thought our performances were quite good and stuck true to the football we wanted to play but the results weren't. We were inconsistent. This year is about maintaining our football and just getting more consistent with our results. If we are going to become one of the big clubs in Japan, we need to finish in those top spots regularly and win silverware. That's our target. It all begins and ends with me with our football. What I do know, when our football is good and we are stable, the results tend to follow."

Postecoglou heads into 2021 on the back of a contract extension following F.Marinos' run to the Champions League last 16, having topped their group.

F.Marinos finished 12th in his first season in 2018 – narrowly avoiding relegation but only being outscored by champions Kawasaki – while they also reached the J.League Cup final as Postecoglou turned the club on their head, leaving a pragmatic approach behind in favour of his entertaining football.

Three years on in his Japan journey, what does the future hold for the ambitious Australian – who has been tipped to make the move to Europe following a brief spell in Greece in 2008?

"Just keep doing what I have been – looking at challenging things and what excite me," he said. "I've been coaching for a while now and I've been pretty fortunate that the clubs I've worked at, we've had some sort of success. I like to think I've left my mark at those clubs. That's what I'm looking for future. Hopefully I have 10-15 years of coaching left in me, whatever the next project is and wherever it is, it's something that will excite me.

"For me, the passion lies in the football. That was the whole challenge of coming to Japan – could I adopt to a different culture, language, the difficulty of the competition, could my ideas work here? It's been hugely satisfying to see that it works, both on a personal basis but for the club because they enjoy the success. Whatever the next move is, it will be a similar scenario."