Leverkusen contenders after Bundesliga bigs' summer slip-ups

The football calendar sometimes seems never-ending. No sooner had transfer deadline day hit than another international period was upon us, and now we're left -- on the back of that -- to pick through the bones of teams' successes and failures on the signings front.

That the Bundesliga restarts with an appetizing duel between Bayern Munich and Bayer Leverkusen on Friday (2:30 p.m. ET, stream live on ESPN+) only adds to the sense of intrigue regarding how the best-equipped squads have acquitted themselves in terms of new personnel.

On this occasion, I feel it's prudent to begin by discussing not the Rekordmeister for once, but instead, the western upstarts who have to my mind stolen the show so far this season. Yes, fans will harp on about Leverkusen never having won very much and hurling insults like "Neverkusen" and "Vizekusen" ("second-kusen") their way, but a tip of the hat is called for based on a strong body of work by sporting managing director Simon Rolfes and his scouting network.

Leverkusen received a substantial billing at the start of the season, and it's fair to say in dazzling wins against RB Leipzig, Borussia Monchengladbach and Darmstadt, they have lived up to the hype. Xabi Alonso is a superstar figure in the technical area while still a relatively inexperienced coach, but there can be no denying the built-in respect he commands in the dressing room based on a fabulous playing career.

- Stream on ESPN+: LaLiga, Bundesliga, more (U.S.)

It has often been the issue on the Bismarckstrasse that too many players view Bayer Leverkusen as a stepping stone to something bigger and more glamorous -- witness the summer exit of Moussa Diaby to the Premier League's Aston Villa -- but a slight change in acquisitions policy with the addition of experienced pros like Granit Xhaka and Jonas Hofmann means a better overall balance while sending a message to the younger players that they're in fact part of a sturdy and effective construction.

Xhaka, the conductor of this orchestra, and Hofmann have already excelled in their short time with the club, but the true Shootingstar (a word commonly used in German football parlance) has been Nigeria striker Victor Boniface, who has netted braces in back-to-back matches and enthralled everyone with his exciting all-action style of forward play. In the current economy, a €16 million transfer (from Union St.-Gilloise) looks like a steal.

There have been so many other positives for Leverkusen so far, from revitalised defenders Jonathan Tah, who starred in Germany's win over France, to Odilon Kossounou to of course the nimble Jeremie Frimpong and jewel-in-the-crown playmaker Florian Wirtz.

Bayern make do with 'thin' squad

A trip to the Allianz Arena represents a colossal test, though, and Leverkusen have only ever prevailed four times in the Bundesliga away to the best team in the Bundesrepublik. Friday will tell us a lot about their progress under a former Bayern favourite.

Bayern's schwarzer Freitag (black Friday) woes at the end of the transfer window have been well documented, missing out on primary target João Palhinha of Fulham, and now they must get on with it despite a squad that coach Thomas Tuchel has described as "thin."

The thinness of the squad really only exists in assessing particular positions -- right-back and defensive midfield most notably. Noussair Mazraoui's reserve in the former slot is to be Konrad Laimer, more a natural central midfield man, although he played well off the bench coming on for Mazraoui in the 2-1 win over longtime Angstgegner (bogey team) Gladbach.

Let's be under no illusions that elsewhere there is something of a Luxusproblem (a problem of luxury). Matthijs de Ligt, Bayern's best defender last season, currently can't get into the team ahead of Dayot Upamecano and Kim Min-jae.

Leon Goretzka, although left out of the Germany squad, has rediscovered his form, which means summer signing Laimer is left looking on from the sidelines. Higher up, how do you accommodate a collection of stars in Leroy Sané, Kingsley Coman, Serge Gnabry, Thomas Müller and Jamal Musiala, once he returns from injury?

Leboeuf calls for Tuchel to do his job and not complain about transfers

Frank Leboeuf discusses Thomas Tuchel not being happy with Bayern Munich's transfer window.

Harry Kane is of course the player Bayern wanted above all others, and his influence so far on and off the pitch has been pervasive. Some will rightly say at a price of more than €100m, that should be a given, but Kane hasn't disappointed with his attributes or attitude.

New sporting director Christoph Freund and his staff will likely return to sign Palhinha in January. It's still a strong Bayern squad with just a few holes visible, and it will be fascinating to see if Leverkusen can exploit those weaknesses on Friday.

Underperforming Dortmund need time

Borussia Dortmund's rebuilding efforts have come in for criticism, and it's easy to see why after three uninspiring performances against FC Cologne, VfL Bochum and Heidenheim. Taking five points from a possible nine is not the start most BVB fans envisaged after finishing level on points with Bayern in last season's Meisterschale race.

Dortmund sporting director Sebastian Kehl had an enormous summer task in replacing Jude Bellingham and Raphaël Guerreiro. He arguably now has an improved defensive situation at left-back with Ramy Bensebaini and more quantity in midfield with Marcel Sabitzer and Felix Nmecha on board.

Too many players have failed to deliver so far, though, including new captain Emre Can, and the final attacking piece -- last season's joint top scorer in the Bundesliga Niclas Füllkrug -- may need time to adapt to BVB's style and vice-versa.

Leipzig accustomed to replacing stars

RB Leipzig, German Cup winners two years running, perhaps have on paper the most difficult assignment given the loss of Laimer, Christopher Nkunku, Dominik Szoboszlai and Josko Gvardiol, plus Marcel Halstenberg and the high earning André Silva.

But planning for the future is something Leipzig do well, and sporting director Max Eberl believes they have made a strong fist of it with players like the pacy, enterprising Loïs Openda, the skillful Xavi Simons and tall striker Benjamin Sesko, who scored a double in the 3-0 win over Union Berlin before starring in this international break for Slovenia.

Castello Lukeba, Nicolas Seiwald and former TSG Hoffenheim man Christoph Baumgartner give them the kind of depth Leipzig have been associated with in their seven previous Bundesliga seasons.

Right now, Leverkusen and Leipzig look stronger than Dortmund in assessing the power of the squads overall, but we must remind ourselves that trajectories can change in this heavy-lifting period of incessant fixtures and international matches between now and the end of the calendar year. Bayern remain the overwhelming favourites.