Ding had already knocked out Ronnie O'Sullivan out of the tournament, triumphing 6-4 in the last 16 to set up an all-Chinese quarter-final with Liang Wenbo.
He swept aside his countryman and dispatch another when he came up against Yan, who had also been on an impressive run to dispatch Neil Robertson and then John Higgins.
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However, the 19-year-old could not replicate the performance in one of the biggest matches of his career so far as Ding completed a simple victory without ever moving through the gears.
Ding had quickly jumped out to a three-frame lead with breaks of 68, 85 and 60 and his opponent never really recovered from the deficit.
He did break his duck before the mid-session interval but Ding quickly restored the three-frame advantage as Yan continually failed to string a break together.
The teenager had failed to break fifty in his victory over Higgins and forced two re-racks in the win against Robertson, but his inability to score heavily cost him against Ding.
It was not until the sixth frame that Yan managed to log his first half-century, with a 95 that should have been a ton but for a missed brown off the spot.
It briefly took him back to within two frames but it was a brief candle for the younger man as Ding capitalised on some uncharacteristically sloppy safety to seal the match and a place in his first final since beating Higgins to the title back in 2009.
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