n front of a crowd of 340, the Peacocks took an early 7th minute lead when Matty Wright was brought down in the box and Ben Adelsbury converted the resulting penalty.
It was 2-0 on the half-hour mark when Ollie Chamberlain slotted past the City keeper.
Winchester pulled one back 7 minutes later through Ollie Bailey.
Nine minutes into the second half, Ross Staley sneaked in at the far post to make it 3-1.
And Wright added the fourth from close range after a low cross into the box.
Newcomers Bristol Manor Farm maintained second place with a 4-2 home win over relegated Cinderford Town.
Troy Simpson put Farm in front after 11 minutes, but less than 2 minutes later, Andy Lewis equalised from the spot.
Simpson scored his second to restore the home side`s advantage, only for Lewis to do likewise for the Foresters after they were awarded another spot-kick.
Jordan Metters and Dean Stamp added two more in the second half to take the game away from the Foresters.
Manor Farm now hold a four-point lead over title favourites Salisbury FC, who were held to a goalless draw at the Raymond McEnhill Stadium by fourth-placed Evesham United in front of a crowd of 650.
Winchester and Didcot Town hold the remaining top six spot, with the Railwaymen eventually condemning bottom side Bishops Cleeve to a tenth defeat in eleven games – and remaining win-less – thanks to a goal from recent signing Felipe Barcelos right on half-time.
The gap between Cleeve and second-bottom Mangotsfield United stretched to six points after the Mangos earned a second win of the season to date, 3-1 at Cossham Street against Larkhall Athletic.
Jay Malpas gave the hosts a 26th minute lead that Kane Simpson doubled almost immediately.
Cory Simpson reduced the deficit 5 minutes into the second half, but Josh Nelmes` third with 6 minutes remaining, killed the Larks off.
Yate Town and fellow strugglers Cirencester Town were involved in an amazing 4-4 draw at the Corinium Stadium.
In horrible conditions, Eugene Keary put the visiting Bluebells ahead after 14 minutes, only for Aidan Bennett to equalise 5 minutes later.
Henry Spalding then gave Ciren the lead 2 minutes after that, but Bristol Rovers youngster Lewis Leigh-Gilchrist sent the teams into the break all-square with Yate`s second in the 34th minute.
But shortly after half-time, Ben Whitehead and then Bennett again took the home side 4-2 up.
However, the visitors fought back and eventually earned a point with goals from Harvey Rivers in the 78th minute and Leigh-Gilchrist again a minute from the end of normal time.
Connor Waldon gave North Leigh an early 5th minute lead at neighbouring Kidlington.
But Lewis Gabbidon after 28 minutes and Lance Williams 5 minutes later turned it round to eventually win it for the home side.
Goals from Toby Holmes after 9 and 87 minutes, then a Jack Alexander own goal in the 76th minute for Wimborne Town prevented Swindon Supermarine from moving into the top six.
Paulton Rovers came from 2-1 down to win by the odd goal in five at Shortwood United.
James Byrne`s 5th minute penalty put Rovers ahead, but Joe White 3 minutes later and Jack Freeman after 32 minutes took United in front.
Tyrone Tucker-Dixon equalised 7 minutes before the break, and then Jack Ball`s 65th minute effort turned out to be Rovers` winner.
Slimbridge returned from their trip to Devon against Barnstaple Town with a 3-0 win.
Marley Thomas after 27 minutes and Adam Mace 5 minutes later sent the Swans 2-0 up at the break.
And a Joe Wilton effort 14 minutes from time sealed victory.
By Steve Whitney
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