Webb struck in the first four frames .
Webb held a commanding lead in the fourth frame but let Williams back in the match after throwing a 3 - 6 - 7 - 10 split in the fifth frame which he failed to convert .
Striking in the first four frames , Webb held a commanding lead in the fourth frame but let Williams back in the match after throwing a 3 - 6 - 7 - 10 split in the fifth frame which he failed to convert .