Complex sentence: Seed won the 2009 NBC Heads-Up Poker Championship, where he took the top prize of $500,000 and improved his overall record in the event to 18-4, an all-time best for win total.
Split into simpler sentences: Seed won the 2009 NBC Heads-Up Poker Championship. In doing so, he took the top prize of $500,000 and improved his overall record in the event to 18-4, an all-time best for win total.