Stephenson has been suspended four games for violating the NFL's policy on performance-enhancing substances, ESPN.com reports. With Stephenson -- who had been in line to start at right tackle for the Chiefs -- now out of the team's early-season mix, Ryan Harris, Jeff Linkenbach and Jeff Allen are the leading candidates to fill in for him. In any case, his upcoming absence represents a significant short-term hit to the team's O-line, a unit that has been struggling of late to begin with.