A year ago, United slumped to 1-0 defeat against Derby County but thrashed the Rams at Old Trafford to book their place in the final.
They will have to turn in a similar performance when they lock horns with Manchester City next week after their nearest rivals came from behind to take a 2-1 lead into the second leg.
Giggs, who has played in 31 consecutive Manchester derbies, prodded United ahead on 17 minutes at the City of Manchester stadium but a goal either side of half-time by United old boy Carlos Tevez swung the tie in favour of City.
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'It was the perfect start,' Giggs told MUTV. 'You always want to go 1-0 up in a cup tie away from home. After that we probably weren't as crisp with our passing and kept playing the ball backwards. We let City back into it, really.
'Last season we comprehensively beat Derby County in the second leg of the semi so hopefully we can do that again. It's going to be tough, City are a good team.
'But there were enough signs, especially in the last half-hour, to suggest we're good enough to beat them.'
Referee Mike Dean was fiercely criticised for throwing City a lifeline when he awarded a penalty after Craig Bellamy tumbled under the attention of Rafael.
Game changer: Tevez in mobbed by his team-mates
Initial contact appeared to be outside the box and Giggs insists it could have been a very different second half had United gone into the break with their lead in tact.
'We felt we were a little unlucky to go into the break at 1-1,' Giggs admitted, 'but we also knew we could play better.
'[The penalty decision] was a turning point. If we'd have gone in 1-0 up it might have been a different story. Sometimes you get decisions and sometimes you don't - you just have to get on with it.
'We created plenty of chances but we didn't have that stroke of luck or the composure in front of goal. Hopefully we'll have that in the second leg - and hopefully we can put the chances away this time.
'After they scored we played well and probably deserved to get that equaliser.'
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