Complex sentence: He made his postseason debut on October 4 in the Division Series against the Philadelphia Phillies and gave up one run (on a home run by Ryan Howard) in one inning in a 10--5 win by Colorado.
Split into simpler sentences: He made his postseason debut on October 4 in the Division Series against the Philadelphia Phillies. Affeldt gave up one run (on a home run by Ryan Howard) in one inning in a 10--5 win by Colorado.