He leads Barca in the last 16 first leg tie in the absence of Tito Vilanova, who is recovering from throat surgery, just over 23 years after Roura damaged ligaments in his right knee during a Supercup game involving the same two clubs.
Although Roura, who was 22 at the time, continued playing for several more years he was never the same and was shunted around lower-tier clubs Murcia, Figueres and finally Sant Andreu before quitting.
"I don't have happy memories of my match against Milan 23 years ago," said the interim coach who has spent much of his career far from the glamour of the Champions League.
"After the injury I couldn't play football any more," he told a news conference on Tuesday. "Milan had a great team then.
"I have returned several times since then as part of the Barcelona staff. A lot has happened since, life always gives you more opportunities," added Roura.
"It's always nice for someone who likes football to come to this stadium although it is always a daunting prospect to play Milan here."
Roura had a low-profile coaching career before being thrown into the spotlight thanks to Barca's policy of stability and promoting from within.
He had a workmanlike career in the Spanish lower leagues which reached a low point when he was fired by third-tier Hospitalat in 2007.
When Vilanova's predecessor Pep Guardiola took over at Barca, Roura joined the staff initially to watch future opponents.
He dismissed the suggestion Barca, who have dominated La Liga this season, are firm favourites to beat a Milan side who are rebuilding after selling a raft of players at the end of last term to cut costs.
"I don't agree at all," said Roura. "I've said it a lot of times - Milan are one of the best, they are a very good team and this is a very difficult stadium.
"I don't understand this heavy favouritism, it doesn't make sense. It's very strange."
