A lot can happen in a short space of time in the Europa League, and four clubs are preparing for their second group game without the coach who led them into the first.
AZ Alkmaar, Tromso, Elfsborg and Maribor have all seen changes, with AZ's decision to sack Gertjan Verbeek coming as the biggest surprise.
It came only a day after they had beaten PSV Eindhoven 2-1 in the Eredivisie.
But neither that, nor a victory over Ajax earlier in the campaign, was enough to convince the club's board that Verbeek was the right man for job.
They sacked the Dutch Cup winner, who took AZ to the quarter-finals of the Europa League in 2012, citing a breakdown of relations between the coach and his players.
Verbeek guided AZ to a 1-0 win over Maccabi Haifa in their Group L opener last time out, but it is assistant Martin Haar who will have the responsibilities against PAOK on Thursday.
Maccabi will look to bounce back from that opening defeat away to Shakhter Karagandy.
If Verbeek's dismissal came as a surprise, Tromso's decision to part with Agnar Christensen was not.
A 3-2 defeat to IK Start has left them in the thick of a relegation fight with five games to play in the Norwegian Eliteserien, and the club have now turned to Steinar Nilsen to steer them through it.
Their Europa League campaign began with a 3-0 loss to Tottenham, but it remains to be seen where Nilsen's priorities lie as they prepare to face FC Sheriff in Group K.
Slovenian champions Maribor will take on English Championship side Wigan in Group D with former striker and assistant coach Ante Simundza in charge after Ante Cacic left the club in the wake of a 2-1 league defeat to FC Koper.
At Elfsborg, Jorgen Lennartsson was giving his marching orders with the team drifting in the Swedish Allsvenskan, sixth and 12 points adrift of leaders Malmo.
Former Sweden midfielder Klas Ingesson will take charge of their Group C match against Standard Liege but the club are yet to name a permanent successor.
Away from the musical chairs, Group A throws up the most interesting fixtures second time around following Swansea's superb 3-0 away win over Valencia.
Michael Laudrup's men will look to build on that at home to St Gallen, but Valencia could have a tough time of mounting an immediate recovery with a tough trip to Kuban Krasnodar on the agenda.
In Group B, PSV Eindhoven must recover from a surprising opening loss to Ludogorets Razgrad when they travel to FC Chornomorets Odesa, while Ludogorets host Dinamo Zagreb.
Salzburg, fresh from a 4-0 romp against Elfsborg, next take aim at Esbjerg in Group C, while the radically reshaped Anzhi Makhachkala face a big ask to get their opening win of the competition as they host in-form Tottenham.
Rapid Vienna and Dynamo Kiev both lost on opening night, making their Group G clash one to watch, while Bordeaux host Maccabi Tel Aviv eager to bounce back from a 3-0 opening loss to Eintracht Frankfurt.
Elsewhere, Rubin Kazan host Zulte Waregem, Fiorentina travel to Dnipro, and Pacos de Ferreira take on Pandurii Targu-Jiu.
Lazio are away to Trabzonspor, Lyon host Vitoria Guimaraes and Eintracht go to Apoel Nicosia.
Sevilla face Sport-Club Freiburg, Genk host Thun and Real Betis travel to the Croatian coastline to take on Rijeka.
Slovan Liberec are at home to Estoril-Praia, while Legia Warsaw face Apollon Limassol.