Watch free daily video highlights from every LV= County Championship match here on ecb.co.uk this summer
Young Sussex batsman Luke Wells hit an unbeaten 108 to help the visitors into a healthy first-innings position at 204 for two after two days of a hard-fought LV= Championship clash at the Kia Oval.
At the ground where his father Alan, the former Sussex and Kent batsman, won his sole Test cap for England against the West Indies in 1995, Wells junior batted with composure and no little style to thwart Surrey's impressive attack for over five hours.
He reached his century just before the close from 234 balls, with 11 fours and a six. It was the 22-year-old's sixth century of his first-class career and his third in as many matches against Surrey in championship cricket.
Responding to Surrey's first-innings total of 351, Wells joined up with Chris Nash to survive an hour against some testing home bowling before the latter fell on the cusp of lunch.
Just two deliveries before the scheduled interval Nash was adjudged lbw by umpire Graham Lloyd when trapped on the crease by a Tim Linley off-cutter. Clearly upset by the decision, Nash marched off showing his bat as if to say he had edged the ball onto his pad.
Former Sussex skipper Michael Yardy teamed up with Wells to add 78 in 34 overs for the second wicket during a tense and attritional middle session when both batsmen survived concerted appeals for catches at the wicket.
The Surrey attack kept it tight, none more so than Linley who sent down seven overs for six runs, as Yardy dug in for 130 minutes in making 23 before falling in the penultimate over before the tea break.
Glancing off his stumps against spinner Gareth Batty, the left-hander picked out Rory Burns at leg slip who did well to cling on to a sharp low chance that made it 104 for two at the interval.
Wells joined forces with his skipper and fellow left-hander Ed Joyce thereafter to frustrate the hosts for the remainder of the day.
The pair added an unbroken 104 for the third wicket - Joyce finishing unbeaten on 51 - to move the visitors within 147 runs of Surrey's first-innings total at the mid-point of the match.
At the start of day two, Sussex took a further hour to claim Surrey's three remaining wickets while the hosts added 50 to bag their fourth batting bonus point.
Chris Tremlett hit a six out of the ground to see his side to the 350 milestone, but was yorked next ball by Chris Jordan to give the former Surrey paceman figures of 5-92 - his second five-for of the summer to date.
Ironically, for home supporters at least, all 10 Surrey wickets were taken by bowlers who once played for the club; Jordan, Steve Magoffin and James Anyon.
Click here for all the latest news from the domestic cricket scene, including exclusive interviews, team news, match reports and photo galleries