Complex sentence: Under Saban, Simpson continued to improve in 1973, setting a single-game rushing record with 250 yards in the season opener against the Washington Redskins and surpassed the season rushing record later in the season with more than 2,000 yards.
Split into simpler sentences: Under Saban, Simpson continued to improve in 1973, setting a single-game rushing record with 250 yards in the season opener against the Washington Redskins. He surpassed the single-season rushing record later in the year with more than 2,000 yards.