Jack Howell's journey in professional baseball began when he was drafted by the California Angels in the 1983 Major League Baseball draft. A third baseman by trade, Howell made his major league debut with the Angels in 1985. Over the next several years, he established himself as a reliable player, known for his solid defensive skills and ability to contribute offensively.

During his time with the Angels, Howell demonstrated his capability as a consistent hitter. In 1987, he had one of his best seasons, hitting 23 home runs and driving in 64 runs. His performance on the field helped the Angels remain competitive in the American League. Howell's versatility allowed him to play not only at third base but also in the outfield and at first base when needed, providing his team with valuable flexibility.

In 1991, Howell took his talents overseas, signing with the Yakult Swallows of Japan's Nippon Professional Baseball (NPB). His stint in Japan proved to be a fruitful chapter in his career. Howell adapted well to the Japanese style of play and became a fan favorite. In 1992, he played a crucial role in leading the Swallows to a Japan Series championship, earning the series MVP honors for his outstanding performance.

After his successful tenure in Japan, Howell returned to Major League Baseball in 1993, signing with the San Diego Padres. Although his time with the Padres was brief, he continued to demonstrate his skills as a seasoned player. Howell later joined the Houston Astros, where he played until 1995. His experience and leadership were assets to the teams he played for during this period.

In 1996, Howell returned to Japan, rejoining the Yakult Swallows. His second stint with the team further solidified his reputation as a skilled player in the NPB. Howell continued to perform at a high level, contributing to the Swallows' success until he retired from professional baseball in 1999.

Throughout his career, Jack Howell was known for his adaptability and consistent performance both in the United States and Japan.