Chelsea touched down in Belfast on Tuesday ahead of their Super Cup showdown with Villarreal.
The two sides will clash on Wednesday night at the South Belfast venue.
It is a massive coup for the Irish FA to attract such a fixture to Northern Ireland, with last season's Champions League winners going up against the 2020/21 Europa League champions.
Windsor Park has undergone a significant transformation in the past few years, and can proudly boast a modern 18,000 seater stadium that is fit to host such glamour games.
A new pitch was also laid for the Super Cup, while neighbouring Midgley Park and the outside of the stadium have been decked in Super Cup banners.
One man to notice the new facilities was Chelsea technical director Petr Cech, whose last appearance at Windsor was back in 2008 when the Czech Republic played Northern Ireland in a World Cup qualifier.
Cech was in nets for the game, which finished 0-0.
When asked for his reaction to Windsor Park's new look on Tuesday night, Cech replied: "It looks slightly different to when I was here last time."
Work got under way on Windsor's redevelopment in May 2014, as part of the NI Executive's regional stadia funding plans.
The project included the demolition of the Railway and South Stand structures which were replaced by new stands that would partially enclose the stadium.
There were also plans to renovate the existing North and West Stands, but the West Stand had to be demolished and rebuilt after cracks were later found in the structure.
Check out Cech's reaction in the video above (fast forward to 4m 20sec)
