Trump had gone into the evening session 4-6 down, but took the opening three frames to move ahead by the mid-session interval.
The two seemed destined to be locked in a tight battle, with Ford keeping up with his illustrious opponent.
Judd Trump races to 100th century of season at World Snooker Championship
Then in the 15th frame, Trump knocked in a break of 131 - his 100th century of the season so far.
Far from seizing the momentum, though, he found himself caught in a vicious circle of four misses and fouls in the next frame, upon which Ford failed to capitalise.
Trump finally potted a red and put together a break of 57 to move 9-7 ahead - but Ford hit back in the 17th frame with a break of 69.
The 18th frame was as tentative and nervy as the opening exchanges, with Ford looking for snookers to hold Trump back from the finish line.
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But Trump had found his range for long pots, using them to excellent effect to finally secure a hard-earned 10-8 win as Ford conceded.
Ford, 36 and something of a journeyman who had only scored one century at the venue in his career, had started the afternoon in surprisingly blistering form.
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He raced ahead in the first frame, and in his second he capitalised on a lucky triple-plant that allowed him to come back from behind into a two-frame lead. That became three when some safety play and attritional approaches left the pair to fight it out on the black, with Ford able to hold his nerve.
Trump then began his fightback, hitting a 104 century in the fourth. A break of 64 in the fifth reduced the deficit to a single frame.
Tom Ford blows 147 chance at World Snooker Championship
Unflustered, Ford answered with a 140 break, the highest of the match and one to double his career centuries at the Crucible.
A break of 61 in the next frame meant that the unfancied player from Leicester had kept the reigning world champion from potting a ball for two consecutive frames.
Showing the determination that brought him a world championship, and some exceptional pre-lockdown form, Trump struck back with two frames, including a hard-fought ninth.
Judd Trump plays three exhibition shots, one right-handed at World Championship
In the afternoon's other game, Ash Carty pulled off a comeback of his own to finish 5-4 down to Stuart Bingham, when it had looked like his opponent would convert a 30-0 lead in the ninth frame into a 6-3 lead.
Meanwhile, the second evening match saw Alan McManus assume a 5-4 lead over fellow vetaran Mark Williams with the pair locked in an enthralling battle.
FRIDAY SCORELINES AND RESULTS
Judd Trump 10 - 8 Tom Ford
Stuart Bingham 5 - 4 Ashley Carty
Ding Junhui 5 - 4 Mark King
Alan McManus 5 - 4 Mark Williams