Sussex produced a run of wickets either side of tea to take control of the match at Northamptonshire. The home side were cursing at 143 for 1 replying to 422 but slipped to 186 for 5 before closing the second day 242 for 6.
The visitors resumed 370 for 6 and claimed maximum batting points before taking 4 for 43 mid-afternoon to raise hopes of a healthy first-innings lead.
Initially, Northants were comfortable in reply to a total built by a mammoth 309-run seventh-wicket partnership. Josh Cobb and Ricardo Vasconcelos shared 136 for the second wicket to provide a confident response.
Vasconcelos, dropped before lunch on 7, went past fifty for the fifth time this summer in 82 balls but having struck Danny Briggs’ left-arm spin for two boundaries in the final over before tea, went to sweep the last ball of the session and was lbw for 83. It was a criminal error and opened an end as Northants’ strong position slipped alarmingly.
Cobb, having entered the game as a concussion replacement for Alex Wakely, cut Briggs past point for his ninth four to raise fifty in 83 balls - just his 11th first-class fifty for his second county - but hooked Abi Sakande to long leg, departing for 62.
Temba Bavuma edged a ball that left him from Mir Hamza and was taken at first slip before Adam Rossington nicked Chris Jordan to second slip to leave Northants 186 for 5, with 273 needed to save the follow-on.
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Rob Keogh, who made 41, and Luke Procter shared a stand of 52 that appeared to be taking Northants to the close with some momentum but three overs from the close, Keogh edged Luke Well’s leg-spin to slip. The wicket ensured Sussex’s grip on the match and Northants suffered another blow when Luke Wood was forced off in the final over after being struck on the side of the head by Jordan.
For the first two sessions of the day, it was a smart comeback by Northants in sunny but breezy conditions. They ended the marathon seventh-wicket stand in just the third over of the day as Brown was trapped lbw by a Wood inswinger for 156. It ended the alliance at 309 - the 13th highest partnership for the seventh wicket in first-class history.
Jordan, dropped third ball of the day at point, could only add eight more before he edged Jamie Overton to the wicketkeeper for a career-best 166. Jamie Overton then wrapped up the innings having Hamza caught at first slip after Nathan Buck had Sakande held at second.
Facing 20 minutes before lunch, Ben Curran drove a full ball to third slip where Phil Salt claimed a very sharp catch. The morning could have got even better for Sussex had Harry Finch taken a straightforward chance offered by Vasconcelos. The miss cost 76 runs but Vasconelos couldn’t take full advantage as Sussex ended the day on top.