Off-spinner Ollie Rayner picked up two wickets but first division leaders Lancashire continued to dominate on the second day of their Specsavers County Championship match at Lord’s.
Alviro Petersen scored 53 runs in the session to reach 158 not out at lunch with Lancashire 404 for 5.
Rayner struck with his first ball of the day, ending a stand of 128 in 38 overs by Petersen and Steven Croft when Croft was caught behind off a mis-timed reverse sweep for 46.
James Fuller pulled off an athletic catch at backward square-leg off a full-blooded sweep by Karl Brown (21) after he and Petersen had added 46 for the fifth wicket.
But it was hard going for the Middlesex seamers on a benign pitch with Petersen timing the ball impeccably, particularly through his strong areas on the off side. So far the 35-year-old has faced 255 balls and hit just eight fours while Liam Livingstone struck successive boundaries off James Franklin in the penultimate over before lunch to take Lancashire past 400.