In 1941, hurling for the Ogden Reds of the Class C Pioneer League, he posted a 21–6 won–lost record, and led his circuit in earned run average (2.21) and winning percentage (.778).

Lambert then missed three seasons, 1943–1945, serving in the United States Army Air Forces during World War II.

[1] Returning to baseball in its first postwar season, he spent 1946 on the Reds' National League roster, appearing in 23 games, 19 of them in relief.

Pitching for a second-division club, his year was marked by two highlights, both starting assignments: complete game victories against the Chicago Cubs on August 31[2] and Philadelphia Phillies on September 19.

[3] Lambert began 1947 on the Reds' early-season roster, but in his first appearance of the year on April 18 against the Pittsburgh Pirates in relief, he was treated harshly, surrendering six hits and seven earned runs in only one inning of work.