Original: At the start of the 1938 - 39 season, after ten full seasons with Boston, he was traded to the Detroit Red Wings, where he completed the season, and played another full one before retiring.
Simplified: At the start of the 1938 - 39 season, after ten entire seasons with Boston, he was traded to the Detroit Red Wings, where he played the rest of the season, and played another full one before stopping.