Littler looked on the brink of a shock early exit after falling 7-2 behind to Wattimena, but he roared back with a six-leg blitz that turned the tie on its head.
The Dutchman refused to fold, clawing his way into a tie-break after saving two match darts, but ultimately succumbed to the 18-year-old's relentless scoring power.
An 11-dart leg and a nerveless finish on double ten sealed a 13-11 victory for Littler, who remains on course for a maiden Matchplay title.
“I’m a World Champion for a reason. I find these gears when I need it,” said Littler, who will play Andrew Gilding for a place in the semi-finals.
“I’ve not felt pressure like that since the first round of the World Championship against Ryan Meikle.
“Jermaine kept putting me under pressure. He was always right behind me, but when I got into the lead, I was determined not to let it slip away.”
Elsewhere, Josh Rock edged out three-time champion Michael van Gerwen in a Matchplay classic. The Northern Irishman overcame a sluggish start and survived a vintage Van Gerwen rally to clinch a breathless 13-11 win.
Van Gerwen had led 4-1 and later 9-6, but faltered when given the chance to stretch his advantage. Rock seized his moment with a stunning 152 checkout and reeled off four consecutive legs to take the lead. Even a 138 checkout from Van Gerwen to level at 10-10 wasn’t enough to derail Rock, who held firm in the closing stages to seal a statement win.
“That’s one of the best games I’ve ever been involved in, without a doubt,” admitted an emotional Rock.
“I think you could see, by my celebrations at the end, what that meant to me. My heart was pumping throughout the whole game.
“Michael always seems to turn up against me, but I’m so happy to get the win.”
Rock now meets Gerwyn Price in a mouthwatering quarter-final, after the Welshman dispatched Chris Dobey with clinical efficiency in an 11-3 rout.
The 2022 finalist was in imperious form, averaging 108.73 in a ruthless performance that saw him claim four legs in succession in just 49 darts. His 73% checkout rate capped a display that was close to his best on the Blackpool stage.
“I don’t think Chris played badly at all,” claimed Price, who also landed eight 180s in an action-packed display.
“I felt like I was on top of my game in the middle part of that match. I was in the zone and I managed to keep my focus.
“I’m confident in my own game. Playing like that will give me even more self-belief, and I feel like I’m getting back to my best.”
The quarter-final line-up is now complete, with action resuming on Thursday evening. Former champion James Wade takes on rising star Gian van Veen, before Stephen Bunting faces last year’s runner-up Jonny Clayton.
On Friday, it’s Littler v Gilding and Rock v Price – a repeat of the recent World Cup final – in what promises to be another electric night at the Empress Ballroom.
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Results
Andrew Gilding 11-5 Dirk van Duijvenbode
Luke Littler 13-11 Jermaine Wattimena
Josh Rock 13-11 Michael van Gerwen
Quarter-finals