Atalanta v Celtic in Champions League: Gasperini & Retegui key men

Atalanta have had to deal with the departure of one of last season’s key men in Teun Koopmeiners, the midfielder who joined Juventus for £46m, and the loss of main striker Gianluca Scamacca to a pre-season cruciate ligament injury.

The defence has been further hit by a series of injuries, the Bosnian Sead Kolasinac the latest of those.

Long-time servants such as Marten de Roon, playing as an auxiliary centre-back recently, and Mario Pasalic have stepped into the breach while the fans have a new goalscorer to adore.

Mateo Retegui, an Argentina-born Italian arrived in the summer for a pretty penny from Genoa and his delightful chipped finish against Venezia on Sunday made it eight in eight league games.

A penalty saved by David Raya in the opening Champions League game is the only blemish on his record thus far. Celtic beware.

And that is before considering the man whose hat-trick in Dublin made Europa League final history, Ademola Lookman.

With three goals at the start of this campaign, including one in the 3-0 Champions League win over Shakhtar Donetsk, the Nigerian will be keen to add to that tally on Wednesday.

Celtic were made to pay for their naive approach in Dortmund. A similar one in Bergamo could yield a similar outcome.