Published: 2019-02-07 04:20:44 BdST
The Brazilian winger, who started in place of Lionel Messi, curled home in the 58th minute to pull Barcelona level after Lucas Vazquez sent Real Madrid ahead early on.
Vazquez struck after just six minutes to silence the Nou Camp at the end of a slick team move, with Santiago Solari’s side impressing in the opening stages.
However, Ivan Rakitic clipped the crossbar with a header as Barcelona fought for an equaliser and Malcom eventually found it when Luis Suarez’s shot rebounded to him off the post.
Messi, who suffered a thigh injury at the weekend against Valencia, appeared for the final half hour but could not help champions Barcelona find a late winner.
The second leg takes place on Feb 27 at the Santiago Bernabeu.