Johan Slager (born 1946) is the original guitar player of the Dutch Progressive Rock band Kayak. He co-founded the band along with Ton Scherpenzeel, Pim Koopman and Max Werner in 1972. He left the band in 1982 after 9 albums, and returned briefly for a couple of performances in the 1990s. When Kayak reunited in 1999, Johan was replaced by Rob Winter.During and after his time with Kayak, Johan played with many Dutch artists.