Middlesex (356 & 111-4) lead Hampshire (438) by 29 runs
Michael Carberry and Rilee Rossouw narrowly missed out on centuries after giving Hampshire a chance of victory against champions Middlesex at the Ageas Bowl.
The pair produced brilliant, brave innings before departing for 98 and 99 respectively.
The hosts were dismissed for 438 - a first-innings lead of 82 - but stayed firmly on top thanks to Kyle Abbott's three-wicket blitz on the visitors' top-order. Middlesex ended the day on 111 for four - 29 runs ahead.
Carberry, who missed the second half of last season as he underwent cancer treatment, began the day on 84.
Two balls after moving to 98 with a thick edge through the slip cordon, he edged behind.
Nightwatchman Abbott reached his maiden championship fifty off 77 balls and put on 80 with Carberry.
Lewis McManus gloved to third slip shortly after Carberry's dismissal brought Rossouw to the crease.
The South African was bashed twice on his injured left hand during his counter-attacking stand with Gareth Berg - the pair adding 86 for the eighth wicket.
Berg was caught and bowled by Dawid Malan, with Brad Wheal caught behind next ball and Rossouw was inexplicably dropped by Malan in the covers.
Fidel Edwards, who injured his hamstring while bowling, completed a walking-wounded partnership for the last wicket.
Brave Rossouw had often needed to lift his bottom hand off the bat but, after taking on a never-there two, he was run out by Sam Robson.
With Hampshire leading by just 82 after the first innings, it looked like a draw was almost guaranteed on the final day - but Abbott had other ideas.
The former South Africa star ripped through Robson with a beauty.
He then accounted for Nick Gubbins with a pearler - his 50th in the championship - angling slightly across the left-hander to kiss the edge of the bat and into Jimmy Adams' hands at second slip.
Abbott almost had a third when Sean Ervine dropped a tough chance at first slip with Steve Eskinazi on six.
Wheal used his impressive pace to take the third scalp as Malan left a hooping in-swinger.
Eskinazi and Adam Voges made a recovery to take Middlesex back into the black, but the former's late swipe behind for 45 off Abbott left Hampshire still hoping for victory.
Abbott said: "I think it is pretty well set for a result tomorrow, we have a big first hour if we can knock over two in the hour and get batting pretty soon would be pretty great.
“They spent a long time in the field which will play to our advantage. We did well today to keep them out there that long and a couple of the wickets this evening were purely fatigue.
“I thought we batted well against some testing bowling but we would have taken that score.
“Sometime I didn’t look at home when Finny was fizzing it around my ears but I enjoy the night-watchman duty – it is an opportunity to bat.
“It is nice to contribute and I thought Rilee was excellent today with a fractured finger – some of the shots were incredible and showed what he will bring to the team.
“I thought he had the second run, I know he is quick through the wickets, but it was a shame. He took it quite badly.
“He took a while to unpad. He realised the opportunity of a hundred but it isn’t the end of the world.
“From what I can understand he was in a lot of pain but he is a tough Afrikaan so he won’t sit down and roll over.
“I was heartbroken there for Carbs. I just wanted to be out there with him when he got that first hundred after what he had been through.
“Carbs has had an amazing attitude since I’ve come back. He seems to be free and it shows in his cricket.”
Middlesex fast bowler Toby Roland-Jones said: “Fair play to Hampshire they batted well today and put themselves in a position to put us under a bit of pressure this evening.
“We’ll certainly need to show a bit of fight in the morning to steady the ship.”