When the Arizona Cardinals walked onto the field at Qualcomm Stadium Tuesday for their first joint practice with the San Diego Chargers, they were without their head coach.
Bruce Arians met with the NFL team's medical staff shortly after arriving at the stadium and complained of stomach pain.
Following an on-site examination, Arians was taken to a local hospital for further evaluation, the team announced.
With Arians absent, Chargers coach Mike McCoy and Cardinals assistant head coach Tom Moore held a pre-practice meeting with both teams in the middle of the field.
Arians, 63, is a prostate cancer survivor but has been in good health since missing one game in 2012 while serving as interim head coach of the Indianapolis Colts with an ear infection.
Filling in for Chuck Pagano, who was battling cancer, Arians was named the NFL's coach of the year for the first time that season. He received the honour again in 2014.