He was the team president of the Houston Astros of Major League Baseball and the owner of the Denver Nuggets of the National Basketball Association.

[1] Shlenker met Roy Hofheinz, the owner of the Houston Astros of Major League Baseball and the Astrodome.

[7] In June 1987, the Major Indoor Soccer League granted a conditional franchise to Shlenker, to begin play in the 1988–89 season.

[8] The team, tentatively named the "Denver Desperados", attracted deposits for 400 season tickets within four months, short of the required 5,000; the franchise was revoked in November 1987.

[1][11] The year before, Shlenker's plans to remove the Mississippi River Museum on Mud Island to make space for bars and restaurants fell through thanks to intervention of the West Tennessee Historical Society, the Mud Island Foundation, and then-Mayor of Memphis, Richard Hackett.

[14] Shlenker suffered a spinal cord injury in a 1998 motor vehicle accident on U.S. Route 395 in Big Pine, California.