Hampshire 336 and 76 for 1 lead Middlesex 361 (Malan 121, Simpson 65, Harris 57, McLaren 4-74, Tomlinson 4-74) by 51 runs
Dawid Malan helped Middlesex to a first innings lead against Hampshire with an attacking century on the third day at the Ageas Bowl.
Malan, who was 40 not out overnight, quickly moved to a 64-ball fifty once the session got underway under mainly blue skies.
He found his progress with eased by some erratic fast bowling from Hampshire seamers Tino Best, Chris Wood and Ryan McLaren. Malan looked in little trouble, after being dropped the day before by Will Smith, punishing the bad balls, while John Simpson held up the other end.
The pair put on 182 for the fifth wicket with a typical defender and aggressor partnership, getting through the morning session without losing a wicket.
Malan reached 121, his three figures came in 134 balls, before he looped legspinner Mason Crane's long hop to extra cover - the teenage bowler embarrassed by his first wicket of the season.
Watchful Simpson, whose 50 came off two balls fewer than Malan's century, departed ten balls later as he edged James Tomlinson behind to Adam Wheater.
The hosts' bowling found their rhythm in the afternoon, with McLaren and Tomlinson in particular finding their form - although they were rocked by a knee injury to Chris Wood which forced him off the field mid over.
McLaren looked fired up, and twice knocked the off stump out the ground with brisk deliveries - Paul Stirling done by one which angled in and Toby Ronald-Jones missing a pull shot.
Tomlinson was rewarded for his persistence by taking his season tally to 12, after taking just 18 scalps in 2015. He removed James Harris for 57 and ended the Middlesex innings when Steven Finn skied to Best at mid-off. Middlesex, who batted a man light due to Adam Voges' concussion injury, led by 25 runs.
Hampshire started their second innings spritely, with Michael Carberry - the scorer of a ton in the first innings - twice slapping Tim Murtagh to the boundary in the first over. But he fell lbw to a full ball from Murtagh for 15 in the seventh over, which may have hit him outside the line.
Leg-before appeals were a common cry throughout the evening as Jimmy Adams and James Vince, who supplied some jaw dropping cover drives, battled through to close. Hampshire led by 51 but a draw remained the most probable result on the final day.