The Indianapolis Star reports that Pagano had been feeling fatigued and got blood tests during the bye week, when the illness was diagnosed. The Colts have planned a press conference for this morning at which they will give more details on his medical condition.
Colts offensive coordinator Bruce Arians will take over as interim head coach while Pagano is out.
Pagano, who will turn 52 on Tuesday, is in his first year as the Colts’ head coach. A Colts official told the Indianapolis Star that while Pagano’s health issue is a concern, the team is optimistic that he will recover.
UPDATE 9:09 a.m. ET: ESPN’s Chris Mortensen reports that Pagano has been diagnosed with leukemia. Doctors have told him he will be hospitalized for six weeks but that he will make a full recovery and return to coaching.