Also looks like it was his physical therapist, not his agent, who vouched for his heavy hydration.

 

"Dear Dr. Lawrence Brown,

 

Zachary Mettenberger was under our care from 2/11/14 to 3/10/14 for the rehabilitation of his left knee. During this time, he reported to us that he was experiencing frequent muscle cramping during the day as well as at night while trying to sleep. Because of this, he was advised to drink as much as 1 to 1.5 gallons of water per day, to increase his consumption of foods high in potassium, and to increase his sodium intake. This was recommended as he was performing rehab and training 6 days a week from 7:30 a.m. to 5 p.m., causing dehydration. This high consumption of fluid was necessary to counteract the dehydration from intensive training sessions and to promote a healthy fluid balance while Zachary was healing from his recent ACL reconstruction.

 

We also recommend that Zachary continues this process throughout his rigorous rehab program to avoid future cramping and possible dehydration. If you should have any specific questions regarding this matter please feel free to contact me.Thank you.

 

Best regards,

 

Jason Eliowitz."



Read more: http://www.baltimoresun.com/sports/raven...z315Mt12M7
 
If he had anything illegal in his system, it still would have shown up even with a "diluted" sample.  It would have been there, only... diluted.  The NFL considers any "diluted" sample, even if having no trace of banned or illegal substances, as a "failed" test.

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