In March 1987, Megadeth started its first world tour in the United Kingdom. The tour had other bands, such as Overkill and Necros, and went to the United States. During the tour, Mustaine and Ellefson wanted to fire Samuelson because of his cocaine addiction. Drummer Chuck Behler played with Megadeth for the last few weeks of the tour. This was because band members thought Samuelson was not going to be able to play for the rest of it. Mustaine and Poland had arguments because Mustaine thought Poland was selling the band's supplies to buy heroin. Samuelson and Poland left Megadeth in 1987 for these reasons. Chuck Behler became the band's new drummer. Poland was replaced by guitarist Jeff Young.