Complex sentence: Despite a two error performance against the San Francisco Giants, Sizemore proved himself to be an adequate shortstop; however, with second baseman Jim Lefebvre not hitting, Sizemore began seeing more time at second by the end of his first month in the majors.
Split into simpler sentences: Despite a two error performance against the San Francisco Giants, Sizemore proved himself an adequate shortstop. Still, with second baseman Jim Lefebvre not hitting, Sizemore began seeing more time at second by the end of his first month in the majors.