The initiative swung away from Lancashire in favour of Middlesex on the last day of the Specsavers County Championship clash at Old Trafford.
Dawid Malan and John Simpson both scored half-centuries as the Championship table-toppers Middlesex built their lead on the final morning against Lancashire at Old Trafford.
By lunch, the pair had shared 112, and the lead had swelled to 235.
Resuming on 72 for four, progress was slow first thing for Malan and Simpson in the face of some probing bowling from Kyle Jarvis and Simon Kerrigan, but the batsmen soaked up deliveries and grew into their innings to give their side a chance to set up a declaration.
Malan, having smacked the Lancashire captain Steven Croft down the ground for six, reached his half-century from 128 balls, with five fours.
Simpson, playing busily and repelling impressive turn from Liam Livingstone’s leg-breaks, brought up his own 50 with a cover driven four off Kerrigan, from his 150th ball.
Middlesex, including the six bonus points they have earned from this match, currently sit four points ahead of Yorkshire (who they face at Lord’s next week) and five ahead of Somerset.