A record seventh-wicket stand of 165 from Nic Pothas and Dimitri Mascarenhas took Hampshire to 480-8 after two days against relegation-threatened Surrey.
Pothas made an unbeaten 137, his second century of the season, the partnership eclipsing the 145 by Percy Fender and Tom Barling for Surrey in 1933.
Mascarenhas hit 18 fours but was denied his first ton for two years when on 99 he was Jon Batty's 500th dismissal.
New signing Shoaib Akhtar looked short of fitness and did not take a wicket.
Shoaib rarely threatened the batsmen and was reduced to bowling off a shortened run in his final spell, sending down only 11 overs in the day.
Alex Tudor, back at Surrey on loan from Essex, looked far more likely in partnership with Jade Dernbach.
Shoaib did take a catch running in from fine-leg, as Liam Dawson top-edged Tudor's bouncer.
Matthew Spriegel dislodged the dangerous Mascarenhas, when a sweep was held by Batty, to record his landmark dismissal, and the slow bowler struck again to trap Chris Tremlett for a duck.
Pothas reached three figures from 162 balls but Hampshire chose to bat on rather than have a few overs at the Surrey batsmen before the close,
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