Young spin bowler Amir Hussain (5-23) helped dismiss the hosts for 90, with Jack Beetham (32) the only Keighley batsman to look at ease.
Undercliffe had set up their latest win by compiling 193-7. Ahmad Raja (59), Hamid Khan (50) and Nawaz Sardar (46) all played important knocks.
Khan and Raja shared in a 100 stand for the second wicket after Australian bowler Andrew King (4-38) had claimed an early wicket.
Keighley’s disappointment at surrendering top spot was compounded when they discovered that in-form Saltaire had defeated Brighouse by 112 runs, a result which earned them 18 points and lifted them into second place.
Amer Ayoub produced a match-winning spell of 6-41 as Brighouse were skittled for 67 in reply to Saltaire’s 179.
Overseas player Israr Ullah (41) and Asif Ayub (33) were the main contributors for Saltaire, while Fakhar Hussain (4-47) and Umar Salim (3-33) were the best of the Brighouse bowlers.
The outstanding individual performance of the day came from Rob Burton of Spen Victoria. Last season’s leading wicket-taker produced a spell of 8-35 as Windhill were bowled out for 85 to seal a 52-run win.
Spen’s 137 owed much to a determined 48 from Peter Jackson as Salman Ali (3-31) and Hanif Khan (3-40) spearheaded the Windhill attack.
The Cavendish Road side struggled to 134-9 in reply as spinner Chris Rhodes picked up 3-35.
Experienced seamer Nigel Hanson took 5-31 as Bankfoot bowled out Hartshead Moor for 150 to seal a 21-run verdict. Overseas player Farhad Ul-haq (39) and Franny Nelson (35) were the pick of the Moor batsmen.
Overseas player Sandeep Bavanaka made an important 69 for Bankfoot as they reached 171-7, despite the efforts of Nasseer Sauldagar (5-32).
Bowling Old Lane beat neighbours Great Horton by three wickets in a low-scoring encounter.
Ahsan Butt (3-11) and Devraj Patel (3-9) were responsible for bowling out Horton for 77. Old Lane struggled in reply but were guided to their modest target by Butt (32no) as Sadaqat Zaman claimed 4-31.