Shula worked with Morrall at the Baltimore Colts before bringing him to the Miami Dolphins, where he played a crucial role as a backup quarterback in the team's 1972 season, which saw them go 17-0.
Morrall stepped in for the injured Bob Griese to start nine matches as the Dolphins recorded the only undefeated season in NFL history, and Shula was full of praise for the 1968 NFL MVP.
"I was very saddened to learn about Earl's passing. All Earl ever did was win games for me, whether it was as a starter or coming off the bench," Shula said in a team statement.
"What I remember the most, of course, is what he did in 1972 when he replaced Bob Griese after Bob's injury and kept our perfect season going until Bob returned in the playoffs.
"But Earl won a lot of games for me in Baltimore as well. And he did it in such a humble way - he was a great team player who would do whatever was asked of him. And he was an outstanding leader who inspired confidence in his teammates."
Morrall won three Super Bowl championships and featured in two Pro Bowls during his illustrious career.