Complex sentence: He came back to the Cardinals after 18 days on May 20, but blew Michael Wacha's 2-1 lead in his debut on May 30, and was demoted a second time to AAA-Memphis the next day.
Split into simpler sentences: He came back to the Cardinals after 18 days on May 20 and blew Michael Wacha's 2-1 lead in his debut on May 30. He was demoted a second time to AAA-Memphis the next day.