Derbyshire 173 (Came 66, Roland-Jones 5-34) and 74 for 3 (Roland-Jones 2-28) trail Middlesex 358 (Stoneman 115, De Caires 80, Holden 68) by 111 runs
Middlesex are on track for the win they need to keep their Vitality County Championship promotion challenge alive going into the final week of the season after maintaining their dominance over bottom-of-the-table Derbyshire, with opener Mark Stoneman making his seventh hundred for the county before revealing he would be leaving at the end of the season.
Having bowled Derbyshire out for 173 on Tuesday, Middlesex replied with 358, with Josh De Caires matching his career-best 80 and Max Holden posting 68 despite a dry, turning pitch that saw six wickets shared among Derbyshire's spinners and 17-year-old fast bowling prospect Harry Moore impress with 3 for 55 in only his second first-class match.
Needing 186 to make Middlesex bat again, Derbyshire lost two wickets in the first five overs of their second innings and another from the last ball of the day to close on 74 for 3.
Stoneman, 37, who began his career with Durham and won 11 Test caps, moved to Middlesex from Surrey in 2021 but has not been offered a contract for 2025.
"Unfortunately, before the last game I was told I was being released at the end of the season," Stoneman said. "I've had a lot of support from the boys over the last couple of weeks so it is good to come in and put in a performance in this game and put a score on the board for them.
"It is frustrating but I've missed out when the other guys have cashed in on a number of occasions. You live and die by your numbers and I guess mine have not been good enough overall. But I want to finish the season on a high. My enthusiasm for the game is as high as it has ever been, so it is good to be able to make a score here."
Middlesex banked maximum bowling bonus points on day one and had looked well placed at 125 for 1 overnight to push for a full set of batting points.
That they were able to take only three of the five on offer was largely down to a morning session that saw Derbyshire's spinners claim four wickets, while the best part of 36 overs yielded only 82 runs.
From 162 for one, four wickets fell for 45. Holden, who shared a 162-run stand with Stoneman, was first to depart, bowled behind his legs by the on-loan Lancashire left-arm spinner Jack Morley, who would finish with three for 76.
Stoneman played magnificently, completing a chanceless hundred from 170 balls, having hit 17 fours, but could little influence events at the other end as Leus Du Plooy - returning to his former patch for the first time since move - was struck in front by off-spinner Alex Thomson, who then bowled Ryan Higgins middle and leg with one that turned sharply.
David Lloyd, the Derbyshire captain, joined in for the last over of the session and was rewarded from his third delivery bowling off spin as Jack Davies edged to second slip.
After lunch, another sharply turning ball ultimately did for Stoneman, who lost his middle stump to Thomson at 234 for 6, before De Caires and Luke Hollman mounted a counter-attack, although one helped by Wayne Madsen, at slip, dropping De Caires on 21 off Morley.
It was after that let-off that runs began to flow more readily against the second new ball, De Caires and Hollman ultimately adding 74 - 53 of them after De Caires's escape.
Their partnership was ended when Moore, the England Under-19 who is exciting Derbyshire's coaching staff, beat Hollman for pace, following up by having Toby Roland-Jones caught off a top-edged hook.
Moore picked up his third when Ethan Bamber's edge was taken diving to his right by 'keeper Brooke Guest before De Caires was leg before to Morley attempting a reverse hit.
Roland-Jones, with figures of 5 for 34 in the first innings, quickly had Derbyshire in trouble at 16 for 2 after Harry Came and Guest were leg before to balls well pitched up, before Madsen and Mitch Wagstaff - in as a concussion replacement for Luis Reece - decided to meet attack with attack and added 42 in four overs before Middlesex took steps to regain control.
Hollman's leg-spin ended their partnership with what became the last ball of the day, having Wagstaff caught behind.
The absent Reece batted and bowled on day one but subsequently complained of feeling unwell, which was put down to a delayed reaction following his involvement in a minor road accident last weekend. The protocols around replacements require the stand-in to be a like-for-like player. As a left-handed, top-order batter, 21-year-old Wagstaff qualifies on one of those counts, but as a leg-spinner rather than a seamer was not permitted to bowl.
