In 2003, the Tigers won the Central League pennant. Igawa made a great contribution with his brilliant performance. He pitched very well and finished with a 20–5 record, a 2.80 ERA, and was third with 179 strikeouts. He was named to the Best Nine, won the MVP in the Central League and also won the Eiji Sawamura Award, the Japanese equivalent of the MLB Cy Young Award.