Complex sentence: Hornish raced in the Sprint Cup Series full-time in 2008, initially struggling in the series, earning eight top-tens and performing no better than his 28th-place finish in points (2009).
Split into simpler sentences: Hornish raced in the Sprint Cup Series full-time in 2008. Hornish initially struggled in the series, getting eight top tens and finishing no better than 28th place in points (2009).