Carlin began his baseball career in 1936 with the Enterprise Browns of the Class D Alabama-Florida League and the Helena, Arkansas Seaporters in the Class C Cotton States League. He also starred on the first baseball team at Southeastern Louisiana College in Hammond, Louisiana. After graduating, he was drafted by the New York Giants and assigned to the Richmond Colts in the Class B Piedmont League for the 1938 season. That December the Giants traded him and Tom Baker to the Washington Senators for first-baseman Zeke Bonura.
In 1939 Carlin started with the Charlotte Hornets, also in the Piedmont League, and had his best season as a batter, knocking in 10 home runs and hitting for a .272 average over 106 games. The following year he played for the Greenville Spinners of the South Atlantic League before being promoted to the Springfield Nationals of the Class A Eastern League.
At age 23, Carling played 11 games, 2 as a third baseman and 9 as an outfielder, for the 1941 Philadelphia Phillies. After the season he enlisted in the U.S. Navy and served as a physical training instructor, petty officer first class, at the Norfolk Naval Training Station during World War II.
As a member of the Navy's "Blue Jackets" All-Star team, Carlin broke open a 5-inning benefit game against the Army unit at New York's Polo Grounds on June 14, 1942. His three-run home run off Hugh Mulcahy in the first paced his side's 4-0 victory. By 1944 Carlin was stationed at the Aiea Heights Naval Hospital in Hawai'i. He played on another All-Star team, helping fellow Birminghamian Virgil Trucks defeat the 7th Army Air Force team in the Pacific World Series.
After his discharge, Carlin attended Southeastern Louisiana University. He returned to professional baseball in 1946 with the Montgomery Rebels of the Class B Southeastern League. He finished the season with the Atlanta Crackers of the Southern Association, but in 1947 moved back down to Class D, with the Enterprise Boll Weevils. His final season was in 1949, with the Gadsden Chiefs.