 Complete the following phrase:  Thornton was eliminated at the first round stage of a World Championship for the first time in his career in 2016, when he could only take three legs off Alan Norris in a 30 defeat. He relinquished an 80 lead in the first round of the Masters to lose 109 against Dave Chisnall. On the opening night of the Premier League, Thornton averaged just 75.68 as Chisnall whitewashed him 70. He only won two matches out of 16 games to finish eighth in the table. Thornton was knocked out in the second round of the 