The FA Cup medal resides alongside its Champions League counterpart, illustrious neighbours flanked by glittering Portuguese league and cup presences.
Elsewhere, adorning his office wall, a scroll bestowing the Freedom of the City for Portsmouth hangs.
Daily forays back in time to a glorious football career which ended so romantically in 2012 at Guimaraes, his home-town club where the journey began.
Mendes remains in football, an agent for MNM Sports Management, with former Rangers boss Pedro Caixinha among his clients.
Yet those playing achievements, including a triumphant 2008 FA Cup final medal, are never far from his heart.
‘I follow Pompey on Instagram,’ he said.
‘Of course, I don’t know anyone there now, but I follow the results and keep watching out for them.
‘That is something you can never switch off. When you play you never switch off the places where you went, especially Portsmouth. I had never played at Wembley before that FA Cup final. The FA Cup is probably one of the most historic trophies in Europe, so winning it was a proud achievement for myself.
‘Especially playing for a team not favourites to win it.
‘We were outsiders, we were Portsmouth, and to get to the final and win the Cup with a club like Portsmouth was full value for what we did.
‘Back in Portugal, the FA Cup final was always on television, but almost every year it was the same four or five clubs who got there. Not in 2008, that was Portsmouth – and everyone should be really, really proud of it.
‘The game was ours. I cannot remember every part of the match but I cannot remember any danger.
‘At the beginning of the season you want to go as far as you can in the FA Cup, see how you progress in the competition. At Portsmouth you needed to be realistic.
‘When I first joined it was about avoiding relegation.
‘Then, after the signings we had, the realistic target to finish in the top half of the table and we came ninth and eighth in successive seasons.
‘We knew that season would probably be the best chance for many years to win the FA Cup. Even if Portsmouth ever reached the final again, it will normally be against one of the top-10 teams that are always there.
‘But we had Cardiff and knew that was a chance to win it and make history.
‘We were quite aware and prepared for the game like the way we had for Manchester United. We didn’t take one inch off the value that the opponents had. We needed to play the game fully committed, fully focused, no matter the opposition.
‘We had a great team at the time anyway and that counted.
‘We knew it was the only chance for Portsmouth to win it in the next who knows how many years – and we did just that.’
Mendes represented a surprise selection for the FA Cup final against the Bluebirds. In what would turn out to be his final season at Fratton Park, he started only 14 Premier League games, with Harry Redknapp preferring a midfield triumvirate of Lassana Diarra, Sulley Muntari and Papa Bouba Diop.
But the former Porto Champions League winner earned a first start in five matches for the last match of the league campaign against Fulham, coming in for Diop.
Then he retained his place for a Wembley occasion which would yield a 1-0 Pompey win, courtesy of Kanu.
Now aged 39, Mendes added: ‘I remember getting to the stadium, the after-match celebrations and the parade the following day was unbelievable, it was unbelievable.
‘Everybody from the city was there along the roads.
‘Kanu was our goalscorer and he was quite a character. His technical ability was incredible, in training he would do something and it was a pleasure playing alongside him.
‘Then there was Harry Redknapp, a manager who gets the best out of players, deals with the staff, the team and everyone around it. You cannot compare him to anyone.
‘I had a great relationship with Harry, as a manager, as a friend, as a man. You can have a fantastic chat with him, a great guy.
‘As a manager he had his good days and bad days.
‘When he was upset, when he wasn’t in the best mood about something, everyone would realise that something we were doing wasn’t right!
‘We knew, he cannot hide his feelings, he’s not afraid to show his feelings.
‘Our team was great, from the goalkeeper to the striker, a fantastic side, and probably only Harry could manage these players playing for Pompey.
‘He built a fantastic squad, full of great guys, full of talent, experience, young players as well. He did a great job.’