Birmingham Bears 202 for 6 (Yates 71, Hain 48*, Davies 46) beat Northamptonshire XXX (Vasconcelos 65, Miles 4-29) by 21 runs
Yates scored 71 off 53 balls (eight fours, one six) and shared a 100-run opening partnership with Alex Davis (46 off 29 balls) a record for the Bears against the Steelbacks.
Freddie Heldreich stemmed the flow of runs by removing Davies and Australian dangerman Glenn Maxwell for 0 in the space of two balls, but while AJ Tye picked up two wickets in the closing overs, Sam Hain blasted 48 off just 27 balls to push the Bears past 200.
Willey conceded just a single off a tight opening over before Yates and Davies went on the offensive. Davies (five fours, one six) rode his luck amid a flurry of aggressive shots as the Bears reached 55 at the end of the Powerplay.
Davies offered a difficult chance on 23 which Tye couldn't hold onto running back. He then miscued Tom Taylor over the keeper's head before Taylor himself put down a straightforward chance off Heldreich.
In between those moments of fortune he mixed some classic drives and late cuts with huge shots over the infield, swinging James Sales high over deep square leg for the first six of the innings.
Yates who had capitalised early on with consecutive boundaries off stray legside balls from Taylor, duly reached his half-century off 38 balls. He brought up the Bears' 100 at the halfway mark by striking Tye for four and then swinging him high over fine leg for an big six.
But Heldreich held his nerve to strike with the first two balls of the eleventh over. First Davies was sharply stumped by McManus before Maxwell was well caught by Tye on the boundary as he aimed a big six down the ground.
Yates was joined by Hain in a stand of 49, the former disdainfully smashing Taylor straight down the ground and smacking him through the covers for consecutive boundaries before meting out similar treatment to Heldreich. Yates' innings finally ended when he pulled Willey high to deep midwicket where Cobb took a stunning leaping catch.
The next two wickets both fell to boundary catches by Taylor off Tye removing Dan Mousley, and Chris Benjamin. Ed Barnard fell to a boundary catch off Willey in the penultimate over before Hain struck Tye for four and a six in the final over to take the Bears past 200.
Vasconcelos motored through his innings. He punched dismissively down the ground and cut powerfully as he reached his half-century off 30 balls. He was particularly severe on Mousley, hitting him for three consecutive boundaries in his first over and two in his second.
Such was Vasconcelos' dominance that Chris Lynn only made 7 out of their opening stand of 41 in 4.2 overs before the Australian was caught off Miles before Josh Cobb also fell cheaply to Mousley.
Vasconcelos looked well set before he sliced one from Miles straight to point with the hosts 81 for three in the tenth over. Saif Zaib played a cameo of 14 but was caught off Miles.
Willey and McManus put on 35 in 3.3 overs before the skipper was caught off Briggs at backward point. McManus picked up the mantle, carving Maxwell away for six and a four before he was caught on the boundary attempting another big shot. When Graeme White became Miles' fourth victim, the game was almost over.