Peter Wright and Simon Whitlock came through thrilling matches and will now face each other in the last four of the PDC World Darts Championship, with both their quarter-finals settled by final set tie-breaks.
Wright trailed 2-0 in the early stages but produced some moments of real quality when he needed them to eventually edge out Wes Newton, who has now lost at the quarter-final stage in three of the last four years at the tournament and by the same agonising 5-4 scoreline.
Whitlock looked on course for a much more comfortable success, but had to withstand a stirring fightback from Ian White before finally scraping through.
Appearing in the last eight for the first time, Wright appeared a little nervy early on and Newton took full advantage, breaking in the very first leg. It would prove decisive as he wrapped up the set in the fourth leg after hitting double-three at the second time of asking.
It was Wright who broke in the opening leg of the second set and he looked on course to level as he won the next as well. But Newton responded with a superb 140 check-out to force a decider and, after Wright had just failed with a 170 finish, he duly took out 45 to double his lead.
The third set also went to a deciding leg, but this time it was Wright who prevailed as he located double-two with Newton waiting on 60 to get himself back into the contest.
Playing with more fluidity, Wright dominated the fourth and, after breaking in the opening leg, he levelled up the match in spectacular style by producing a superb 164 finish.
A 95 checkout followed at the start of the fifth set from Wright, but he would be pegged back and, in another deciding leg, missed two darts at double-18 to allow Newton to nip in and pinch the set against the darts.
The next followed a similar pattern with Newton going two legs up and having a dart at tops for a 4-2 lead in sets. But he missed and Wright grabbed his chance with both hands, coming up with a crucial 120 checkout under intense pressure to take the deciding leg and tie the scores once again at three sets each.
Nip and tuck
With the momentum on his side, Wright was always in control of the seventh after opening it with a 107 checkout and would go on to take out 62 in clinical style to get his nose ahead in sets for the first time.
But Newton hit back in the best possible style as he swept through the next without dropping a leg to draw level, wrapping up the set in the third leg with a magical 170 checkout.
That ensured a see-saw contest got the deciding set it deserved and it was no surprise to see a tie-break ensue after the players shared the first four legs - although Wright spurned a golden opportunity to seal the deal as he missed four darts for the match in the third of them.
But he eventually got over the line by taking the eighth leg, breaking Newton's throw with a fine 121 checkout, finished on the bull.
"I could have made it easier for myself in the final set, but I forgot about the mistakes I made and just got on with things, and that attitude worked," said Wright.
"To reach the semi-finals of the biggest event in the game, shows all the practice I've put in and the changes I've made to my darts have paid off in a big way."
Whitlock headed into his encounter with White having not dropped a set in his previous two matches and maintained that record as he roared into a 3-0 lead on the back of some clinical finishing.
Although he dropped the next as White finally got on the board, he looked to be closing on victory as he took out 78 to move 4-1 ahead in sets.
But Staffordshire thrower White refused to lie down and incredibly took the next three to force a decider which swung first one way and then the other, before the Australian prevailed by taking the sixth leg.