John Ludwig Welaj (May 27, 1914 – September 13, 2003), pronounced "Weli," according to newspapers of the 1930s,[1] was an American professional baseball outfielder and executive.

He played in Major League Baseball (MLB) for four seasons between 1939 and 1943 for the Washington Senators and Philadelphia Athletics.

Welaj (pronounced WELL-eye, according to a twenty-first-century source[2]) was a native of Barr Township, Cambria County, Pennsylvania, who threw and batted right-handed and was listed as 6 feet (1.8 m) tall and 164 pounds (74 kg).

After 1957, Welaj served in the front offices of both of Washington's 20th century American League franchises.

From 1973 until 1984, he served as the Rangers' director of stadium operations, after which he retired as a full-time employee at age 70.