The Swans go into the second leg of their semi-final tie against Chelsea with a two-goal advantage, having beaten the Blues at Stamford Bridge earlier this month.
However, the Spaniard is adamant that his side must put in a good display at home if they are to reach the final of the cup.
"If you had told me five and a half years ago in League One that I would be top 10 in the Premier League and fighting Chelsea to get to the final at Wembley for the Capital One Cup I would have said it was impossible," said Rangel.
"I think throughout all these years we have built great teams and you can see now that we are enjoying it on the pitch, and this will be one of those occasions when we can put in a good shift and hopefully get through.
"We can become legends, we can make history. It is one of those games we have been waiting for for a long time."
Swansea host Chelsea at the Liberty Stadium in the competition on Wednesday.