Complex sentence: Nastu began his professional baseball career in 1977 pitching for the Cedar Rapids Giants in the Midwest League and the Waterbury Giants in the Eastern League; the next season he was promoted to the AAA Phoenix Giants in Pacific Coast League.
Split into simpler sentences: Nastu began his professional pitchingl career in 1977 with the Cedar Rapids Giants of the Midwest League and the Waterbury Giants of the Eastern League. The next season, he was promoted to the AAA Phoenix Giants of the Pacific Coast League.