Is this the season Bayern's dominance of the Bundesliga finally ends?

It isn't exactly the best sign of harmony on the eve of a new season when your best player comes out and slams your entire summer transfer strategy.

But Robert Lewandowski clearly felt he would be carrying a little too much of the load for Bayern Munich and didn't fancy toeing the party line.

'I think we need three new players,' he said last week. 'We lost three players in attack with Franck Ribery, Arjen Robben and James [Rodriguez] and so far we have not had a [proven] new signing in that area.'

There is typically an aura of invincibility about Bayern that, when combined with a ruthless efficiency both on the field and in the transfer market, explains why they have won seven consecutive Bundesliga titles.

But as the new season dawns in Germany, there is sense that for the first time in several years, Bayern look genuinely vulnerable. Lewandowski's comments were just the latest evidence things aren't entirely groovy in Bavaria.

After winning the Bundesliga by margins of 25, 19, 10, 10, 15 and 21 points between 2012-13 and 2017-18, Bayern were rattled by Borussia Dortmund last season before ultimately scraping home by two points.

This time around, there is an increasing belief that Dortmund can and will break Bayern's vice-like grip on the Meisterschale.

Normally, Bayern have their principal transfer business done and dusted before the squad even report back to their Sabener Strasse base for pre-season training.

This summer, their market dealings have been pretty chaotic. Fair enough, they concluded the £68million purchase of Atletico Madrid defender Lucas Hernandez - a World Cup winner with France - in March.

And it was way back in January they reached agreement with Stuttgart to buy another French World champion - Benjamin Pavard - for £31.4m.

So far, so efficient.

But their mission to sign the kind of attacking talent Lewandowski was speaking about this summer has so far completely failed.

Indeed, given they knew a year ago that stalwarts Robben and Ribery would be ending their time with the club, fans and onlookers alike are stunned a proper contingency plan isn't in place.

They tested Chelsea's resolve with various bids for Callum Hudson-Odoi, only for the 18-year-old to sign a new five-year contract to play under Frank Lampard.

Then there was Bayern's pursuit of Manchester City winger Leroy Sane, the player earmarked as the successor to Robben and Ribery when it came to creating goals.

Despite Sane's desire to leave City, Bayern allowed the saga to drag on all summer and had just about agreed terms to sign him for £90m when the Germany international damaged his anterior cruciate ligament in the Community Shield.

Sane's injury means Bayern now need a Plan B when it comes to attacking acquisitions and time isn't on their side given their first Bundesliga game is on Friday night and the German window shuts on September 2.

It hasn't exactly helped the mood that Dortmund have shown a Bayern-like efficiency in finalising their squad nice and early for the new season.

They have been able to ape the Bayern strategy of signing every half-decent player at the other clubs in the Bundesliga by bringing in Julian Brandt from Bayer Leverkusen, Nico Schulz from Hoffenheim and Thorgan Hazard from Borussia Monchengladbach.

They even convinced Bayern to sell them the respected centre-half Mats Hummels and his return to the Westfalenstadion should help patch up the defensive deficiencies that cost Dortmund last season.

The contretemps between Kovac and Rummenigge provided another hint at a rumoured power struggle behind the scenes when it comes to the manager brought in from Eintracht Frankfurt at the beginning of last season.