Surrey 280 (Ansari 74, Davies 67, Allenby 4-47) and 50 for 2 lead Glamorgan 209 (Allenby 52, Meaker 4-57, Linley 3-24) by 121 runs
Surrey, with a lead of 121 and eight second innings wickets remaining, still have vague hopes of adorning Graeme Smith's return to the capital with victory in his first match in charge - and much of that it is down to Stuart Meaker.
On the previous day, England chairman of selectors James Whitaker was present at The Oval, and the talk was of him keeping tabs on Meaker in particular. After Mitchell Johnson's exploits over the winter, the emphasis on speed is greater than ever, and Meaker is one of a handful of bowlers singled out for possessing raw pace.
An injury-plagued 2013 campaign meant Meaker had to have surgery on both his right knee and right shoulder in the winter. After a good pre-season behind him that featured a 6 for 6 against Cambridge MCCU and his work here on the third day, there will be many at Surrey and beyond who will be buoyed by his progress.
Entrusted with the new ball, Meaker's first wicket was that of Gareth Rees, snaffled by Graeme Smith with a combination of bucket hands and torso. He had to wait till after lunch for his next key involvement which proved crucial to Surrey's cause, as he took three wickets for 12, in a fast yet focused five overs from the Vauxhall End.
Four balls into his new spell he had the wicket of Will Bragg, who had looked balanced and in good touch for his 38, before he pressed forward and edged through to Steven Davies. With his tail up, Meaker started to go through the gears. He held an aggressive line but, where others with his pace might have been tempted to dole out some short stuff, he had seen enough to know he was doing the right thing.
His next wicket of Murray Goodwin was perhaps the most valuable. Both Goodwin and Jim Allenby had scored the bulk of Glamorgan's Championship runs last season - 2,379 - and were the likeliest paring to launch a comeback. A combination of pace and a bit of movement into Goodwin meant the partnership only managed 10.
Meaker then had his fourth wicket with the next ball, as he sent Mark Wallace back for a golden duck. There was some confusion over the wicket, as a stifled lbw shout turned into an appeal for a catch at first slip. It was only after Smith had taken the catch and raised his arms that the umpire sent Wallace on his way, much to the dismay of the Glamorgan skipper.
Earlier in the day, Meaker had played a fine hand, initially supporting Zafar Ansari who was finally dismissed by the 259th ball he faced, as Michael Hogan came around the wicket to find his outside edge. His innings featured 216 dot balls, of which it seemed about 99 were left - it might not have been pretty, but it was a great display of patience and sheer bloody-mindedness: Smith would have approved.
Meaker might well have added more after Ansari's departure, but he was run out when Chris Tremlett failed convincingly to turn down the offer of a third run. The bails were removed at the non-strikers end, with Meaker halfway down the pitch.
To Tremlett's credit, he atoned for the error with some big hitting, including three fours and a six off one Graham Wagg over. His effort with the ball started poorly, with his two overs before lunch going for 14. He went into the break with a kick of the turf in annoyance, but returned with more pace and conviction in the afternoon session.
That Glamorgan passed 200 owed much to a handy 24 from Ruaidhri Smith and a fine half-century from all-action hero Allenby. In Surrey's first innings he had bowled 30 overs for just the fourth time in his 159 first class innings, leading the way with four wickets. Here, he counter-attacked superbly, punishing any width and cashing in when Meaker and young Tom Curran over-pitched or offered too much width.
Curran in particular struggled when he was brought into the attack in the 36th over as Allenby, and then Wagg, went after him. Soon, his captain had repositioned himself at mid-off and Curran had his maiden Championship wicket, as Wagg mistimed, allowing Rory Burns to run around to point and take the catch.
Curran would eventually bring the innings to a close with a smart caught and bowled, but the wickets of Burns and Smith, both to the impressive Wagg, will have tarnished Surrey's day. It could have been worse, as a big shout for lbw against Sibley was turned down, with less than five overs left in the day.