County Championship D2, Worcester, day two: Derbyshire 163 & 27-4 (at close); Worcestershire 301
Kabir Ali and Steve Rhodes took the leading roles to leave bottom club Derbyshire facing the prospect of a seventh Championship defeat.
They put on 104 for the eight wicket as Worcestershire built a 136-run lead with Ali hitting 68 off 89 balls and then taking 3-18 with the new ball before rain ended play early.
It was a tremendous effort by a player whose family are mourning the death of his two-week-old nephew.
Resuming on 155-6, the home side lost Gareth Batty for 32, when he was lbw to left-armer Kevin Dean.
But Ali was quickly into his stride, striking 11 fours, with Rhodes content in the supporting role.
The last three wickets went down for only seven runs after lunch, two of them to left-armer Mohammad Ali, but Derbyshire were soon deep in trouble as they began their second innings.
Ali found an excellent line and won lbw decisions against Michael Di Venuto, Chris Bassano and Rawait Khan before Nantie Hayward had Steve Selwood caught behind for a duck
It proved to be the South African's first and last delivery of the day as the weather closed in and sent the players back to the dressing rooms with Derbyshire still 111 in arrears.
Worcestershire: S D Peters, A Singh, Kadeer Ali, B F Smith (Capt), V S Solanki, A J Hall, G J Batty, S J Rhodes (Wkt), Kabir Ali,
M S Mason, M Hayward.
Derbyshire: M J Di Venuto, C W G Bassano, R M Khan, M Kaif, S A Selwood, D G Cork (Capt), G Welch, K J Dean, K M Krikken (Wkt), Mohammad Ali, L J Wharton.