Wilson pitched in all or part of 12 seasons (1945–46; 1948–49; 1951–58) for five Major League franchises and six different cities: the Boston Red Sox, St. Louis Browns/Baltimore Orioles, Philadelphia Athletics, Boston Braves/Milwaukee Braves and Chicago White Sox. He began his pro career during World War II in 1943 in the Red Sox' farm system and in his second year, 1944, he won 19 games with the top-level Louisville Colonels of the American Association. He made the Red Sox' roster coming out of spring training and started 21 games for them during the season's first four months. In his 21st start, on August 9 at Briggs Stadium, Wilson worked into the tenth inning of a 3–3 game. With one out, Detroit Tigers' slugger Hank Greenberg hit a line drive back through the box that struck Wilson in the head, fracturing his skull and sending him to Henry Ford Hospital. The injury sidelined Wilson for the rest of the campaign and he would pitch only one more game for the Red Sox, on April 23, 1946.