A brilliant unbeaten century by Alec Stewart and remarkable Sunday-best figures of 5 for 10 by Ben Hollioake helped steer Surrey to an unlikely victory over Derbyshire at The Oval.
Stewart hit 112 as he pulled Surrey back from 16 for 4 to 221 for 6 in their 40 overs, while Derbyshire could reach only 171 in 36.5 overs to give Surrey their third successive AXA Equity and Law League win.
The highlight of the Derbyshire innings was Devon Malcolm's Sunday-best innings of 42, which contained three sixes and three fours.
The seam bowling of Hollioake, 18, proved too much for the Derbyshire batsmen, but it was his brother Adam who sparked the collapse. He failed to hold on to a return catch from Chris Adams but succeeded in deflecting the ball on to the stumps at the bowler's end, with Dean Jones out of his ground backing up.
He then took a fine catch to dismiss Adams, giving Ben his first wicket, and the slide was on. The brothers went on to pick off the opposition at will with Ben enjoying a spell of 5 for 6 in 31 balls.
Stewart shared in a fifth-wicket partnership of 118 with Nadeem Shahid (47) as he turned Surrey's fortunes around, while Brendon Julian clubbed four huge sixes, two each off Kim Barnett and Devon Malcolm, in his 23- ball 41 in a stand of 87 with his captain.
Stewart's unbeaten hundred, the seventh of his career and his second this season, contained a dozen boundaries and occupied 121 balls.
Middlesex maintained their unbeaten Sunday league record with a six-wicket success over Yorkshire with 25 balls to spare.
Before Paul Weekes had got off the mark, he off-drove Darren Gough, but Alex McGrath put the chance down at deep mid-off and Weekes went on to be Middlesex's top scorer with 50.
Their victory target was 168 and Yorkshire, who batted first when David Byas won the toss, will have been disappointed with an insufficient total on a lively Lord's pitch.
Craig White did help to speed things up and his 38, which included five fours, came off only 35 balls, but he was the only one who seemed capable of introducing the necessary acceleration.