It will be 855 days since Frank Lampard last stood in a Champions League dugout as Chelsea boss and his new team tasked with toppling Real Madrid is unrecognisable.
Lampard has a mountainous challenge to revive his goal-shy team against the European champions and a narrow defeat to Wolves on Saturday - albeit just days after he had taken charge - did little to boost confidence levels ahead of Wednesday's trip to the Bernabeu.
Thomas Tuchel credited Lampard for "laying the foundations" for European glory in 2021 as the German claimed the ultimate prize following the club legend's mid-season sacking.
But while Lampard is more than familiar with his surroundings and certain players, the dynamic of the squad is entirely different to what he was building at Stamford Bridge.
He has returned to a chaotic new era at Cobham with the new owners sanctioning expensive new signings but appearing to lack any long-term vision.
Lampard's last Champions League game in charge was a group-stage dead rubber against Russian side Krasnodar, with Chelsea already through to the knockout stages.
That second string side included 10 changes and a first start for teenager Tino Anjorin - now on loan at Huddersfield Town - as well as Billy Gilmour and Timo Werner, who have since departed.
But the contrast in the team inherited from Graham Potter to Lampard's first Chelsea side is best evidenced in the previous Champions League fixture, a 4-0 rout at Sevilla.
Olivier Giroud stole the show that night in December 2020 with all four goals in a full-strength front three alongside Christian Pulisic and Callum Hudson-Odoi.
Now starved of goals, Lampard is expected to now rely on new faces Raheem Sterling and Joao Felix to keep Chelsea in the tie in Madrid.
Kai Havertz has been virtually anonymous for large parts of the season and his struggles have been indicative of a blunt Chelsea attack.
But the German started in a midfield three during Chelsea's last Champions League win under Lampard in Seville, and could be backed once more to step up in Spain.
Jorginho and Mateo Kovacic were Lampard's preferred options in the midfield three in his previous regime and started in one of his side's most convincing wins over Sevilla.
Kovacic could line up again alongside a returning Lampard favourite in Mason Mount, while this is also the type of night club record signing Enzo Fernandez is expected to prove his worth.
And it will be all change at the back, with Cesar Azpilicueta still out with a head injury sustained in February and Kepa set to start ahead of the returning Eduoard Mendy.
Lampard used Antonio Rudiger and Andreas Christensen as his preferred centre-back pairing two seasons ago but summer signings Wesley Fofana and Kalidou Koulibaly are likely to be tasked with keeping out Madrid at the Bernabeu.
Rudiger barely featured under Lampard but helped Tuchel conquer Europe when he left and will now be looking to make a telling statement with victory over his former club for Los Blancos. Christensen, meanwhile has since joined Barcelona on a free transfer.
Lampard had Emerson at left-back for his last Champions League win and will be relying on Ben Chilwell and Reece James to provide attacking presence down the flanks.
It is likely that only Havertz and Kovacic will remain in the starting team from Lampard's last memorable Champions League night, but victory with a misfiring squad over two legs against Real Madrid would prove one of his finest Chelsea achievements.
