Complex sentence: Although he again split time between the two clubs the following season, by 2000, Vokoun established himself in the NHL, though he initially only saw limited action as the back-up to starter Mike Dunham.
Split into simpler sentences: Although he again split time between the two clubs the following season, by 2000, Vokoun was in the NHL to stay. However, he saw only limited action as the back-up to Mike Dunham.