Jimmy Adams led a determined Hampshire response after second-placed Northamptonshire had built an impressive first-innings total around Rob Keogh's maiden double-century.
Adams ended a run of poor personal form with an unbeaten 71 as Hampshire closed the second day of the LV= County Championship Division Two match at the Ageas Bowl on 160 for two in reply to Northamptonshire's 438.
Hampshire still trail by 278 runs and need another 129 to avoid the follow-on but the wicket, so difficult on the first morning, has flattened out in the sunshine.
Northants, needing every point to close the gap on leaders Lancashire, resumed the second day at a healthy 323 for six and it was another 18 overs before Hampshire finally ended a morale-sapping stand of 187 between the inexperienced Keogh and Matt Spriegel.
Spreigel had hit eight fours in his 76 when edged James Tomlinson behind, only for Northamptonshire to prosper further thereafter.
Trent Copeland went to a Bates leg-side catch off Ruel Brathwaite, his third wicket of the innings coinciding with the signing of a contract until the end of next season.
Keogh and Jon Batty added another 51 for the ninth wicket before both departed in the space of eight balls, the latter giving Bates his sixth catch.
The former’s almost-eight-hour vigil then came to an end as Liam Dawson snaffled a return chance.
Keogh, whose previous best score had been 44, faced 383 balls, hit 32 fours and fully deserved his standing ovation from the small crowd and both sets of players having come to the crease when batting was most difficult with the visitors 24 for three.
Brathwaite, who had been on trial from Durham, was the most successful bowler with 3-112, his performance monitored by members of Hampshire's 1973 championship-winning squad celebrating their achievement of not losing a match in that entire season.
Among those attending was the famous opening pairing of Barry Richards and Gordon Greenidge, who would have relished the easy-paced wicket on which Michael Roberts and Adams began the task of replying.
Roberts was the first to go for 36, beaten for pace by Steven Crook.
However, a partnership of 97 between Adams and Dawson allayed fears of a Hampshire collapse, ending only when the latter hit Spreigel's off spin to Copeland at midwicket.
Neil McKenzie was 22 not out at the close with a draw looking increasingly likely.