Hampshire 451 (Rossouw 120*, Vince 103, Onions 5-96) and 237 for 5 (Weatherley 126*) drew with Lancashire 411 (Vilas 134, Davies 115, Clark 82)
Division One strugglers Lancashire and Hampshire played out a high-scoring County Championship draw at Old Trafford, with both now facing the prospect of a relegation fight later this summer.
The players shook hands at 4.50pm to confirm the result when the visitors declared on 237 for 5 in their second innings, leading by 277.
Opener Joe Weatherley's unbeaten 126 off 260 balls, which saw him bat through the whole day, represented his maiden first-class hundred.
This draw means that both sides leapfrog Yorkshire to leave them second bottom in Division One after they suffered a seven-wicket defeat to leaders Surrey at Scarborough.
Yorkshire are four points behind Hampshire and three behind Lancashire, but they have only played seven and have a game in hand on both.
At the start of the final day here, James Vince's side resumed on 66 for 2 - a lead of 106.
An attritional morning saw Hampshire add only 69 as bowlers continued to work hard. Allrounder Jordan Clark made the breakthrough in the 12th over of the day when Sam Northeast was bowled for 10.
Lancashire had an early lbw decision against Weatherley adjudged not out. In all, he batted for six and a quarter hours, with Hampshire's second innings starting late on day three.
This was his second century for the county, with his first coming against Kent in the Royal London Cup. The 21-year-old had scored three first-class fifties heading into this game, including one against Surrey two rounds ago.
After tea, Weatherley and Ian Holland (26 not out) batted through, sharing an unbroken 73 for the sixth wicket to advance from 164 for 5 following the departure of Rilee Rossouw.
Lancashire have another relegation battle next up when they welcome Yorkshire to Old Trafford at the end of July for the first of two vital Roses clashes.
That will be their final Championship match at the venue this season as the club will be relaying the outfield ahead of next year's World Cup and the Ashes Test.
With the Vitality Blast on the horizon, Hampshire will have to wait until August 19 to play Championship cricket again when they will take on Nottinghamshire at home.
For now, though, their attention will turn towards Lord's when they will welcome back Dale Steyn, who was rested from this fixture.
Liam Dawson will also be back amidst his stint with the England Lions, for whom he taken eight wickets in three one-day matches against the A teams of India and the West Indies over the last week.