Lewis moved to the top of Group A and set up a tie with Michael van Gerwen tomorrow after a 5-2 win over Ross Smith.
Thornton on his return to TV action performed well in defeating Dimitri van den Bergh as he sprung a surprise against 'The Dreammaker'.
Lewis started exceptionally taking out 74 and 95 with two brilliant roars from 'Jackpot' to take a 2-0 lead with an early break of throw.
More missed darts went for Smith and Lewis continued to strengthen his grip on the tie at 3-0 up. 'Smudger' who was having a terrible time on the doubles finally eased his fears but Lewis went one away on double eight. A 42 checkout saw Lewis conclude proceedings though in what was a brilliant win for 'Jackpot'.
The first two legs were shared before Van den Bergh missed two doubles in the third and Thornton hit double seven to lead 2-1.
Van den Bergh though levelled it up from there cleaning up 80 to square proceedings up. Both players produced brilliance though taking out 102 to break throw for a 3-2 advantage and this was confounded by a terrific 160 checkout from 'The Thorn'.
He went one away holding his throw but despite that, Van den Bergh hit a 106 to force a decider at 4-4. Thornton finished it off from there to claim a brilliant win on his return to TV.
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Darren Webster (96.7) 3-5 (98.87) William O'Connor (D)
Gerwyn Price (88.21) 5-3 (84.24) Mikuru Suzuki (C)
Ian White (88.94) 5-2 (90.42) Steve Lennon (B)
Gary Anderson (94.75) 5-1 (86.2) Dave Parletti (D)
James Wade (93.72) 5-2 (86.78) Wesley Harms (B)
Michael van Gerwen (97.89) 5-2 (83.34) Jim Williams (A)
Adrian Lewis (87.48) 5-2 (86.11) Ross Smith (A)
Dimitri Van den Bergh (95.44) 4-5 (91.46) Robert Thornton (C)
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