Riverdale student and baseball pitcher Clay Riggs continues to improve in a Nashville hospital. The 16-year old is now off a ventilator as he continues to recover from a rare problem that caused him to have trouble breathing following knee surgery. Riverdale baseball players are wearing a sticker with his number 24 on their helmets as they play this season. Riggs is expected to remain in Vanderbilt Children's Hospital for awhile as he slow recovery continues.