Earlier this month, the team said D'Alessandris had been hospitalized for an acute illness and would require treatment for an extended period. Ravens head coach John Harbaugh said at the time D'Alessandris had surgery earlier in the summer and some complications had arisen from it.
D'Alessandris, who has been with the Ravens since 2017, coached for 45 years including stops in the Canadian Football League, the World League, and college football before coming to the NFL. He was an assistant with the Kansas City Chiefs, Buffalo Bills and the then San Diego Chargers ahead of coming to Baltimore.
"Coach 'Joe D' was a man of integrity and a man of faith," Harbaugh said in a statement Sunday. "He made us all better. He was our reader at team mass, and he was loved by all here. He was a great coach and a good man - the kind of person who you are honored to have as a friend. I admired him, loved him and am going to miss him, because 'Joe D' was a joy."
Earlier this month, the Ravens hired George Warhop to take over D'Alessandris' role on an interim basis.
"Today is a sad day for the Baltimore Ravens," Ravens general manager Eric DeCosta said in a statement. "'Joe D' was a rock, a great coach and a better person. He cared about the team deeply, exhibiting a relentless passion to excel while displaying genuine love for his players. I especially treasure my conversations with him, talking about football and life.
"I will always remember standing back with Joe on the practice field and watching him up close with his players. Coach was the consummate teacher and friend, and I will miss him deeply. Our thoughts and prayers go to Joe's daughters and family and everyone touched by Joe's remarkable spirit."