During an exhibition game in 1982, as a member of the Triple-A Salt Lake City Gulls, Allen drew a walk to win the game against the Major League Seattle Mariners.
Allen was placed on the Mariners' 40-man roster on November 6, 1982 as a part of what the Mariners' General Manager Dan O'Brien rebuilding plan.
He made his Major League debut on May 1, 1983 at the Kingdome against the Baltimore Orioles. He went one-for-four in the game. In his only big league season, Allen hit .223 with four home runs, ten doubles and 21 RBIs in 86 games.