Clay sat out Sunday's training camp practice as a rest day, John Murphy of BuffaloBills.com reports.
This could be a frequent occurrence throughout the summer for Clay, as his knee may not be 100 percent for quite some time. He's also got quite a bit of wear and tear on his body, and with there being a big drop-off between Clay and whoever wins the No. 2 tight end job, you can bet the team will closely monitor his reps.