Conversation so far:
barcelona vs real madrid who has more wins
Barcelona has more competitve match wins than Real Madrid.
is there a name for the barcelona vs real madrid rival team matches?
El Clásico is the name given in football to any match between fierce rivals FC Barcelona and Real Madrid.
when do madrid and barcelona face off next?
Madrid and Barcelona played March 01, 2019.
who is the top scorer between madrid and barcelona?
Lionel Messi is the top scorer between El Clasico.

Question: are there players that have played for both teams?
Self-contained rewrite: are there players that have played for both madrid and barcelona?