<p>Williams was ruled unable to play in the huge Saturday night clash, with a spot in the NBA Finals at stake, due to a left hamstring strain, according to the injury report.</p><p>The Thunder star wing has been hampered by a hamstring issue since the start of the playoffs.</p><p>He exited after just seven minutes in game two of the Western Conference finals series against the Spurs, and missed games three, four, and five.</p><p>Williams managed just 10 minutes in Thursday's emphatic 118-91 loss, and did not feature in the fourth quarter.</p><p>Defeat to San Antonio tied the best-of-seven series at 3-3, with the final game taking place in Oklahoma City on Saturday.</p><p>Williams had played a vital role in the Thunder's successful run to the NBA championship last year.</p><p>The victors on Saturday will play the New York Knicks for this year's title.</p><p>The Knicks are in superb form and well rested, after sweeping both the Cleveland Cavaliers and Philadelphia 76ers in an 11-game winning streak on their way to the finals.</p>