Did he play on any Santana albums?
John McLaughlin and Carlos Santana played on two albums both recorded in 1973. "Love Devotion Surrender" (Santana and McLaughlin contribute on every song. "Welcome" John McLaughlin contributes on 1 track titled "Flame Sky"
Using the Wiki Discography links, "Love Devotion Surrender" is listed on the John McLaughlin (they both play on all songs) discography under Collaborative Albums.
"Welcome" is listed on the Santana Discography and McLaughlin plays on one track #8 Flame Sky.