Patrice Evra lamented a missed opportunity and an extended hangover from Manchester United's Champions League exit as his wait for a first FA Cup winner's medal continued.
The France international is on course to secure a fifth Barclays Premier League title with United, but remains without a victory in the FA Cup following holders Chelsea's 1-0 win at Stamford Bridge yesterday.
"We were really sad to lose in the Champions League - this game hurt us a lot when we lost against (Real) Madrid," Evra, who moved to Old Trafford in January 2006, told ITV.
"We really wanted to win the double and for a lot of players, even myself, we haven't won the FA Cup. It was an important trophy."
A spectacular Demba Ba strike secured Chelsea a semi-final berth against Manchester City and extended United's wait for a first FA Cup triumph since 2004.
City are United's next opponents in the Premier League, next Monday.
Victory for United at Old Trafford against their second-placed rivals and the defending Premier League champions would enhance their lead to a near-unassailable 18 points with seven matches remaining.
Evra added: "Now we're going to focus on the league. It's nearly done. We have to win a few games."
Following the Champions League and FA Cup exits, United's sole focus is the league.
The prospect of a first double since the 1999 treble-winning season was near after 11 minutes of the original quarter-final tie with Chelsea last month.
United showed no signs of rustiness following the Madrid loss the previous Tuesday as goals from Javier Hernandez and Wayne Rooney saw them accelerate to a two-goal lead, but Chelsea responded to force the replay.
Evra believes the Old Trafford clash is where United conceded the tie.
"It's a big disappointment," he said.
"I think we lost it on the first leg (game). We have to be realistic. We gave the game away.
"We were winning 2-0. they came back and we drew 2-2.
"After that we said 'okay, we get another chance to win at Stamford Bridge'.
"But they deserve to qualify and it's a massive disappointment for us and for the club."
Striker Wayne Rooney was again absent for United with a groin injury picked up on international duty with England.
Manager Sir Alex Ferguson expects Rooney to return to face City.
The Stamford Bridge defeat will linger in the memory for Evra's fellow defender Chris Smalling, whose focus now turns to claiming derby success.
"At the start of the day, we saw this replay as a new challenge and a fresh start so you can't think about the lead in the first match and what might have been," Smalling told MUTV.
"We need to make sure that we remember this defeat next season and not let it slip again.
"It will take a couple of days to get over this because a lot of us came into it with great confidence and we felt we were going to win this game.
"At least we have a good game next Monday but we need to make sure that we rally together and win this title with aplomb."