Middlesex 269 (White 99, Stevens 5-79, Klaassen 4-44) lead Kent 146 for 5 (Denly 70*) by 123 runs
West Indies paceman Miguel Cummins bagged three wickets as Kent were made to work hard for their first-innings runs on day three of their Bob Willis Trophy clash with Middlesex in Canterbury.
Joe Denly top-scored for the hosts with an excellent unbeaten 70 as he and nightwatchman Matt Milnes made it through to stumps on 146 for 5 to trail the visitors by 123 runs going into the fourth and final day.
Kent lost makeshift opener Marcus O'Riordan and his partner Daniel Bell-Drummond within 13 overs as they started their response to Middlesex's workmanlike total of 269 all out.
Bell-Drummond fended at a lifter from Cummins to glove a catch through to the keeper, then, steaming down the Nackington Road slope, Cummins drew O'Riordan outside off, fencing away from his body at another short one to be caught at fourth slip.
Soon after tea, and with the score on 57, last week's double-century maker Jack Leaning blotted his copybook by reaching on the drive at a wide one from Ethan Bamber to be caught at point.
Denly, back in the Kent side after his exclusion from England's Test squad, teamed up with Sam Billings to cash in on several loose deliveries from James Harris and Bamber in an attractive fourth-wicket stand worth 39.
Billings added 20 to the partnership before his loose back-foot waft against the extra pace of Cummins - one of the few overseas players on show this season - flew to the keeper to make it 96 for 4.
Denly maintained a cool head down the other end to reach an attractive fifty in two hours with a clipped four through midwicket against dangerman Cummins. The right-hander faced 83 balls and hit nine fours.
Denly combined with Oli Robinson to help see off Cummins after the Bajan claimed 3 for 41 from his three excellent spells but his replacement, Martin Andersson moved one late off the seam to have Robinson held at slip by Stevie Eskinazi at the second attempt.
At the day's start, reduced cloud cover and the softer, older ball, ensured seventh-wicket partners Robbie White and Harris found batting conditions far more favourable than their counterparts had during the opening two days.
The pair frustrated Kent for much of the opening session adding 93 useful runs as White posted a 151-ball 50 with eight fours scored in a shade over three hours and soon moved past his first-class career-best of 69, scored for Loughborough MCCU against Northamptonshire at Wantage Road in 2017.
His near five-hour vigil spread over 220 balls was ended on 99 by the 11th delivery with the second new ball and an agonising juggled catch in the cordon. Prodding half-forward to a Darren Stevens away-swinger, White turned to watch as the outside edge flew to second slip where Leaming clung on to the chance at the third attempt.
Harris, the former Kent loanee, had reached a patient 41 from 128 balls when he too was out-foxed by Stevens. Prodding forward to a legcutter, Harris pushed inside the line to have his off stump plucked out.
Fred Klaassen came up with a near identical delivery to clip off stump and account for left-handed Cummins and give Kent their third bowling bonus point.
Stevens duly wrapped up his 28th five-wicket first-class haul by trapping last man Thilan Walallawita lbw low on the front pad with an inswinger to end the innings after 108 overs. Klaassen, with 4 for 44, recorded career-best first-class figures.
