Anderson, the 27-year-old No.9 seed was first up and set the tone with a 9-4, 6-7, 2-1 defeat of the No.16 seed, Nicky Brett from Cambridge. "I dominated the first set but Nicky was always getting in before me in the second and played some amazing running bowls. I don't think he missed anything."
With match against him in the tie-break, Anderson killed a tightly packed head and, though he did not get a bowl within 15 inches of the jack in the replay, he won through because Brett failed to reach the target area.
His opponent tomorrow will be Gourlay, the No.4 seed who was in superb form against John Price, the No.12 seed from Wales, turning in the most precise, consistent performance of the event so far.
Having enjoyed straight-sets wins over Australia's Kelvin Kerkow and Alex Marshall, the five-time champion, already, he coasted to a 11-2, 12-4 win. "John looked focused and I knew I would have to get in with my first bowl if I was going to make any impact," he said. "I stepped my game up and was really pleased."
Foster, from Troon, was depicted as the 'Terminator' on the BBC pre-match billing and lived up to it in his 11-3, 9-5 destruction of the No.7 seed, Norfolk's Mervyn King. Having won the pairs and mixed pairs earlier this week, he is going for a clean sweep of titles and could equal the record of five singles title held by his best friend and pairs partner Alex Marshall.
Foster, who won his fourth title two years ago, said: "It was without a doubt the best I have played"
He will play Walker, the WIBC world singles winner who scored a hard-earned 7-6, 7-7 win win over the No.10 seed Robert Paxton. "When I went 7-3 up in the second set, I told myself just to settle down and stay calm.
"I'd like to thank David Gourlay for giving me advice about the rink and my opponents, and for letting me use his bowls; he's been great."