Defending champion Trump must come from behind to keep alive hopes of retaining his World Snooker crown as he trails Kyren Wilson.
The world number one, seeking a remarkable seventh ranking event success of the season, is 10-6 behind in his quarter-final tie against Wilson.
Trailing 5-3 from the opening session, a frustrated Trump was unable to level as the pair initially traded frames.
Wilson responded to Trump's knock of 73 with a break of 65 to maintain his two-frame lead.
Trump, who beat John Higgins in last year's final, again reduced the deficit to a single frame but then blew the chance to level at 6-6 by missing a costly final black.
The pattern continued as Wilson ensured he could not trail overnight with a superb 94, the highest break so far of a century-free contest, to go 8-6 ahead.
He then pulled away, taking the final two frames to leave Trump facing an uphill battle on Tuesday.
Look away now, Judd Trump fans! 🤦♂️#ilovesnooker @Betfred pic.twitter.com/dbVG8Wfnkg
— World Snooker Tour (@WeAreWST) August 10, 2020
Elsewhere, three-time champion Mark Selby moved to within just two frames of the semi-finals following a dominant evening display against Neil Robertson.
Resuming 5-3 ahead, Selby won six of the eight frames on offer in the second session to take an 11-5 overnight lead in the best-of-25 clash.
He closed in on victory with a fine break of 76, one of only two 50-plus breaks in a low-scoring affair following the resumption of play.
The action on Tuesday morning sees Ronnie O'Sullivan and Mark Williams resume, with the former trailing 6-2, while Anthony McGill returns to the table, 7-1 to the good over Kurt Maflin.
