KABIR Ali's career-best score of 84 not out carried Worcestershire to 395 all out before Durham replied with 146 for three on the second day of the Championship match at Stockton.
Kabir's previous best was an unbeaten 51 at Northampton last year, but he produced a mixture of quality strokes and streaky ones in thrashing 14 fours and two sixes off 86 balls.
After losing two partners with the total on 41, Durham skipper Jon Lewis was more circumspect in reaching his fifth championship half-century in five innings.
He found a useful ally in Gary Pratt, who made 38 in a stand of 99 before he edged Gareth Batty to slip.
Having barely looked like taking a wicket in the first 26 overs, Durham grabbed four in the last seven before lunch as Worcestershire slipped from 250 for three to 258 for seven.
It started with Ben Smith surrendering to the first ball of a new spell from Javagal Srinath, whose gentle loosener was skied to fine leg.
Resuming on 39, Smith had progressed serenely to 81 off 125 balls, putting on 101 with Vikram Solanki.
Durham generally bowled too short on the slow pitch, although Steve Harmison performed with good control until his figures were spoilt by a last-wicket stand of 49 in five overs.
After 25 overs he had two for 35, but in four more overs thick edges and hopeful swipes saw him concede 34 more runs before he removed Nantie Hayward's off stump. The South African number 11 had six fours in his 28 off 21 balls.
Danny Law was Durham's worst culprit, with Smith cutting him for three fours in one over just after reaching his sixth first-class 50 of the season with a similar stroke.
Solanki drove Vince Wells through extra cover for his eighth four to reach 50 but then the rot set in.
After Smith's exit South African Andrew Hall lasted only seven balls before losing a stump to Srinath.
Solanki edged to Andrew Pratt and Harmison pinned Steve Rhodes lbw.
Michael Gough began Durham's reply by pulling Hayward for a six and a four. But the South African bowled him for 22 and Gordon Muchall edged the next ball to Rhodes before Lewis dug in.
Rain delayed the start of play today.
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