Former Chicago Bears quarterback Bob Avellini, who spent all nine of his NFL seasons in the Windy City, died Saturday. He was 70 years old.

The Bears announced that Avellini lost a battle with cancer.

"Bob was one-of-a-kind, a fierce and tough competitor," the Bears said in a statement. "He’s perhaps best remembered for leading the Bears on an improbable run in 1977 to our first postseason appearance in fourteen years. He will be missed."

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In 1977, both Avellini and Walter Payton, the Bears’ star running back who reached the Hall of Fame, had their best career seasons.

Payton was certainly the beating heart of Chicago’s offense, rushing for a league-high 1,852 yards with 14 touchdowns on the ground.

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But Avellini had a career-high 2,004 yards on 154 completions with 11 touchdowns over 14 games.

As the team's statement said, the Bears hadn’t made the playoffs in 14 years until 1977, when they finally broke the drought. However, the Bears were blown out by the Dallas Cowboys, 37-7, and Avellini threw four interceptions to one touchdown on 25 attempts.

Avellini had a 23-27 regular-season record in 73 games from 1975 through 1984, throwing for 7,111 yards and 33 touchdowns.

The Queens, New York City, native was in the same draft class as Payton, with the Bears picking Avellini 135th overall in the sixth round of the 1975 NFL Draft out of Maryland.

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The Associated Press contributed to this report.