Patrick Joseph Mullin (November 1, 1917 – August 14, 1999) was a Major League Baseball outfielder for the Detroit Tigers from 1940 to 1941 and 1946 to 1953. Born in Trotter, near Connellsville in Fayette County, Pennsylvania, Mullin was signed by the Tigers before the 1937 season as a 19-year-old amateur free agent. A left-handed hitter who threw right-handed, Mullin was listed at 6 ft 2 in (1.88 m) and 190 pounds (86 kg).
Mullin reached the major leagues at age 22 in the final week of the 1940 season, going hitless in four at bats. The Tigers won the American League pennant in 1940, but Mullin did not play in the World Series. He started the 1941 season in the minor leagues at Buffalo, but was brought back up midseason and made a big impression, batting .345 with a .400 on-base percentage and a .509 slugging percentage. In just 54 games, Mullin had 76 hits, scored 42 runs, and 21 extra base hits.
Based on his performance in 1941, Mullin appeared to be a rising star. However, World War II intervened and Mullin joined the United States Army, missing four full seasons during the prime of his athletic life from ages 25–28.
Mullin returned to the Tigers after the war in 1946 and became a solid performer. His best seasons were 1947 and 1948, the only seasons he played in more than 110 games. In 1947, Mullin was among the American League leaders with 28 doubles and 49 extra base hits. He was elected to the American League All Star Team and finished the 1947 season with a .459 on-base percentage, a .470 slugging percentage and an OPS (on-base plus slugging) rating of .829.
In 1948, Mullin was again chosen for the All Star Team. He finished the 1948 campaign with a .385 on-base percentage (driven by 143 hits and 77 bases on balls) and a .504 slugging percentage—8th best in the AL. His OPS rating in 1948 was .889 OPS—7th best in the AL behind the likes of Hall of Famers Ted Williams, Joe DiMaggio, and Lou Boudreau. Mullin was also among the 1948 league leaders in triples (22), home runs (23), and at bats per home run (21.6).
After the 1948 season, Mullin played largely as a reserve outfielder and left-handed hitting pinch hitter. On June 26, 1949, Mullin hit three home runs in a single game. Mullin had 57 pinch hitting appearances in 1953. Mullin retired at the end of the 1953 season, a month shy of his 36th birthday. In ten major league seasons, Mullin played in 834 games for the Tigers, 637 as an outfielder and the rest as a pinch hitter. He finished with a career .271 batting average, 676 hits, and 385 RBIs, a .358 on-base percentage, .453 slugging percentage, and .811 OPS rating.
Mullin remained in baseball after his playing days ended as a scout, minor league manager and (from mid-1963 through 1966) first-base coach for the Tigers, and a coach for the Cleveland Indians (1967) and Montréal Expos (1979–81). He died at age 81 in Brownsville, Pennsylvania, and is buried at Lafayette Memorial Park, in Brownsville, Pennsylvania.