Williams was drafted into the United States Army in April 1918, and appeared in only two games for the Browns that season. He returned to the Browns in 1919 and hit .300 with 6 home runs in 65 games. In , Major League Baseball outlawed specialty pitches such as the spitball and experienced a subsequent jump in the league batting averages as well as home runs. In Williams' first full season as a regular player in 1920, he posted a .307 batting average along with 10 home runs and 72 runs batted in. He continued to improve in 1921 with a .347 batting average with 24 home runs, 117 runs batted in and a career-high .429 on-base percentage.