After playing in his country with 12 de Octubre, Olimpia and Independiente, he went on to spend most of his professional career in Portugal and Russia, starting out at Benfica.

[5] He also found the net against FC Porto in a 1–1 draw on 25 March 2012, also at home,[6] and finished the campaign as the team's top scorer.

[7] For 2012–13, Benfica manager Jorge Jesus decided to recall Melgarejo and reconvert him into a left back, also immediately placing him as a starter.

In July 2013, it was widely reported that Liverpool had agreed a deal to sign Melgarejo on loan, with a view to making the move permanent at the end of the season,[15][16] but no transfer took place.

[23] On 2 March 2019, more than five years after his last selection, Melgarejo was called by manager Eduardo Berizzo ahead of that month's friendlies with Peru and Mexico.