Surrey 189 for 3 (Borthwick 73*, Stoneman 45) trail Middlesex 347 for 6 dec (Gubbins 192, Simpson 53) by 158 runs

Scott Borthwick's four-hour unbeaten 73 anchored Surrey's 189 for 3 from 67 overs in the Bob Willis Trophy's London derby at the Kia Oval following an imaginative Middlesex first innings declaration on 347 for 6.

Borthwick was joined in stands of 71, 69 and then an unbroken 40 that occupied almost 24 overs by Mark Stoneman, Will Jacks and Jamie Smith as Surrey's top order battled hard on a sluggish pitch that did not make strokeplay a straightforward business.

Stoneman's 45 took him 88 balls, with nine fours - three of them in one Tim Murtagh over - while Jacks played the punchiest innings of day two with 36 from 50 balls, including a six and five fours.

Smith, though, took a long time to get going, with Nathan Sowter's leg spin proving particularly hard to score from with just 22 runs coming from his 11 overs. After facing 44 balls, Smith still only had a single to his name but, to his credit, he refused to get flustered and, by stumps, had fought his way to 15 not out.

Borthwick, who batted throughout the afternoon and evening sessions and has faced 183 balls, hitting ten fours, played with great determination and did not play a false shot until he flapped at a short ball from Miguel Cummins on 50 and was fortunate to see it drop to the turf midway between the slips and third man.

Thilan Walallawita, Middlesex's Sri Lanka-born 22-year-old left-arm spinner, claimed a maiden first-class wicket on debut when Stoneman lifted a cut to backward point in his sixth over.

The left-handed opener looked disgusted with himself for the mistake after he and Borthwick had built a solid foundation after Ryan Patel had fallen for just 4 in Murtagh's second over.

Murtagh, on his 39th birthday, saw keeper John Simpson dive to his left to take a brilliant low catch when Patel's edge gave Middlesex early reward for their declaration with 8.3 of their maximum 120-over first innings allocation still unbowled, and which left Surrey with three overs to negotiate before the lunch interval.

Jacks swung and swept Walallawita for fours as he accelerated smoothly, but was then pinned leg-before by an inswinger from James Harris.

On 264 for 4 overnight, Middlesex earlier struggled to push on against some accurate Surrey bowling. Choosing not to take a second new ball that had become available towards the end of the first day after 90 overs, Surrey concentrated on containment and not even Nick Gubbins - who resumed on 150 - could break the shackles.

Gubbins was finally out for 192, from 315 balls with a six and 19 fours, when he sliced Rikki Clarke to backward point in a vain attempt to get Middlesex to a fourth batting bonus point. Simpson, who had helped Gubbins to add 131 in 36 overs for the fifth wicket, was also dismissed, leg-before sweeping at Borthwick's leg spin for 53, just ahead of the declaration.