If there is something in the oft-repeated truism that the best managers create their teams in their own image then the identities of Jurgen Klopp and Rafa Benitez are obvious with Borussia Dortmund and Napoli. Klopp's haywire, wildly energetic and furious personality is matched by his side's frenetic, high-tempo style of play, while Benitez has moulded his new club towards the boxy, at times mechanical approach characteristic of the coach's manner.
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On paper, this clash may have been more interesting when the latter used the unorthodox 3-4-3 favoured by Benitez's predecessor Walter Mazzari, but context and circumstances still make this most high-profile and high-tension match on Tuesday night. Quite simply, Dortmund have to win -- a defeat will mathematically eliminate them -- and having practically lost a grip in the Bundesliga with a 3-0 defeat to Bayern Munich on Saturday, will be keen not to confirm the regression to the mean that many expected.
But this is also a significantly important encounter for Napoli, another test of their credentials under Benitez. After two successive defeats to Juventus and Parma either side of the international break their pace in the title race has suffered, the latter loss their first at home in nearly a year. It was an apathetic, lethargic performance, made worse by Marek Hamsik's injury just minutes after entering the fray from the bench. The Slovakian is out of Tuesday's match.
Dortmund, too, have injury problems, and were without their entire first choice back four against Munich. They held out for sixty minutes, surprising given Manuel Friedrich was featuring in their back line having been signed on a short term contract. Yet the central defender cannot feature in Europe so the question of who partners Sokratis at the back remains an unanswered one, with Sven Bender possibly dropping into the back four to cover for the crisis, just as he did in the reverse fixture between these two sides when Mats Hummels was forced off through injury.
Still, it's worth questioning whether Napoli's lone absence is equal to Dortmund's desolation. After all, Hamsik is the key creative player under Benitez, the one that leads their transition from defence to attack -- his all-round game has improved significantly since the early days on the right hand side of Mazzari's 3-4-3, and he's a far more complete, creative attacker than he's probably given credit for.
Goran Pandev is a significant downgrade, and as a consequence, Napoli's attacking moves don't feel quite as fluent. The outside-to-in runs of the wingers, Lorenzo Insigne and Jose Callejon, aren't as effective, Gonzalo Higuain's movement in behind not as incisive. Those two factors were the key in the last clash between these two sides, as Dortmund struggled to contain the constant threat of Insigne and Higuain getting in behind their back four - but part of that was because Hamsik's threat meant Dortmund's midfielders were concerned with closing him down quickly, thus opening up space elsewhere for other players. To illustrate the point, Napoli failed to muster a real chance in the eighty-one minutes without him against Parma.
However, Dortmund are in the most patchwork of situations. They will come out with energy and intense pressing but over ninety minutes Benitez's side probably have the greater depth to cope with their respective downward spiral.