Ollie Pope fell seven runs short of a career-best first-class score, but his innings of 245 at the Kia Oval helped Surrey take the upper-hand over Leicestershire in their LV=Insurance County Championship match.
The England batsman resumed day three unbeaten on 92 and was in imperious form on his way to another double hundred in a knock which lasted 272 balls before he was stumped in search of a 31st boundary.
Pope, who top scored with 34 during a difficult winter tour of India, was able to celebrate a three-figure knock for the first time since he hit a maiden Test century away to South Africa in January last year.
Bob Willis Trophy holders Essex have taken their Group One fixture with Durham into the final day and could pull off an unexpected win after they set 168 for victory.
Half-centuries from Paul Walter (77) and Ben Allison (52) got the hosts up to 330 in their second innings at Chelmsford, in spite of Brydon Carse's five-wicket haul, and the visitors ended on 60 for three to set up a dramatic finale.
Elsewhere in Group One, Matt Critchley continued to impress for Derbyshire and followed up a day-one hundred with a five-wicket haul to dismiss Worcestershire for 305 before he almost hit another century.
Critchley was dismissed for 84, but his score has helped the home side build up a 353-run advantage ahead of the final day.
Warwickshire have a similar chase at Trent Bridge and need a further 248 runs with seven wickets in hand after Stuart Broad helped restrict them to 85 for three at the close.
The seamer took a solitary wicket while fellow England bowler Olly Stone caught the eye with three for 66 to bowl out Nottinghamshire for 260 in their second innings, setting a total of 333 for the away side to clinch victory.
Gloucestershire's seam attack put them in sight of a first win at Taunton since 1993 on the third day of their Group Two match with Somerset at the Cooper Associates County Ground.
Centuries from Sam Northeast and Ian Holland put Hampshire in a strong position to wrap up victory on Sunday in their match against Middlesex at the Ageas Bowl.
Lancashire will go into the final day of their Group Three clash with Northamptonshire looking to chase down a victory with seven wickets required to seal a first win of the season, with Steven Croft's unbeaten 103 the undoubted highlight for the hosts on Saturday.
Elsewhere, Kiran Carlson scored his second hundred of the match as Glamorgan brought themselves back into the contest against Sussex.
