Victory for Manchester United in the Europa League final could be the launchpad of a successful era for the club, according to manager Ole Gunnar Solskjaer.
The England centre-back travelled as part of a 26-man squad but did not train in Poland on Tuesday and is likely to sit out United's eighth major European final.
United have won five of them – overcoming Benfica, Bayern Munich and Chelsea to lift European Cups, Barcelona to win the Cup Winners' Cup and most recently Ajax in the 2017 Europa League final – with their two defeats coming in Champions League finals against Pep Guardiola's Barcelona in 2009 and 2011.
Success on Wednesday against Unai Emery's LaLiga outfit would secure the first major trophy of Solskjaer's reign and he hopes it can prove to be a catalyst for bigger things at Old Trafford.
"We have five wins in Europe," the Norwegian said. "We've lost twice to Barcelona.
"These are big nights for us. It might be the stepping stone for something better to come, a bright future because this team is a young team.
"It's a team that we've rebuilt over the last couple of years, so hopefully this is the start of something more."
The likely absence of Maguire leaves Solskjaer without his captain and first-choice centre-back.
The 28-year-old sustained ankle ligament damage earlier this month when Aston Villa's Anwar El Ghazi awkwardly landed on him.
Joining Maguire in the stands will be Sir Alex Ferguson, the club's former manager responsible for two of their Champions League successes and the Cup Winners' Cup victory.
Solskjaer scored the winning goal in the 1999 final against Bayern Munich on May 26 as Ferguson's side lifted Europe's premier club competition on what would have been club great Sir Matt Busby's 90th birthday.
And exactly 22 years on Solskjaer expects his players to rise to the occasion as they look to deliver another success on the continent.
He said: "Of course Sir Alex is with us, we know the 26th of May is Sir Matt's birthday, but the players, when they sign for Man United, they sign to win trophies.
"They accept the challenge of being the best because this is the best club in the world, so that's the pleasure of the pressure of Man United. That's something they are ready for because they wouldn't have signed here if they weren't top players."