Mueller played in 57 career games for Buffalo, with 32 starts. He had 238 rushes in his career with Buffalo, accumulating 901 yards and 4 touchdowns. His longest career run was of 20 yards. With 4.2 attempts per game, Mueller averaged 3.8 yards per attempt and 15.8 yards per game. Mueller also tacked up 28 receptions for 169 yards and a touchdown in his career, with a 6.0 yard per reception average. His longest career reception was of 30 yards. Mueller also fumbled nine times in his career.
Mueller also returned punts and kicks for Buffalo on various occasions. In his career he had 6 returns for 93 yards and no touchdowns. His longest return was of 20 yards.