Middlesex 319 for 5 (Stoneman 83, Fernandes 83, Broad 3-65) beat Northamptonshire 317 for 9 (Shaw 76, Miller 73, Zaib 58, Hollman 3-49) by five wickets

Mark Stoneman and Nathan Fernandes shared a stand of 128 to get Middlesex's Metro Bank One-Day Cup campaign up and running with victory over Northamptonshire Steelbacks at Radlett.

The left-handed duo were joint top-scorers for the home side with 83 apiece before Martin Andersson (35 not out from 23 balls) and Jack Davies (31 not out from 17) completed the job with 11 deliveries to spare.

Gus Miller struck a career-best 73 from 68 for the Steelbacks, with Prithvi Shaw and Saif Zaib also scoring half-centuries before Justin Broad hammered an unbeaten 38 from just 20 at the back end of the innings, enabling his side to post 317 for nine.

But, although Broad took three for 65, including two wickets in as many balls, it was not enough for the visitors - who now slip behind Middlesex at the foot of Group A after three consecutive defeats.

Having won the toss and chosen to bat, the Steelbacks suffered early setbacks as both Emilio Gay and Ricardo Vasconcelos perished to edges behind off pacy left-armer Noah Cornwell (two for 54).

Shaw was soon into his stride, however, overcoming the often unpredictable bounce to slam a series of boundaries and pulled Ishaan Kaushal for the first six of the game as he sped to his half-century from 33 deliveries.

The India international (76 from 58) shared a partnership of 77 with George Bartlett, only for the pair to depart in successive overs - each repeating strokes they had previously been fortunate to get away with and enabling Josh de Caires to take his tally of catches to three.

De Caires soon snapped up a fourth when Lewis McManus drove Henry Brookes to mid-off, but Northamptonshire's sixth-wicket pair rebuilt steadily, with Miller the more aggressive as he struck the ball cleanly and powerfully.

Having advanced beyond 50, Miller slog-swept Luke Hollman over the fence before cutting him to backward point later in the over, while Zaib - having taken an hour to find the boundary - also began to accelerate.

Although Zaib holed out for 58, Broad's late flurry lifted the Steelbacks well above the 300 mark, with the final over from Brookes disappearing for 22.

Middlesex began their reply briskly, with Joe Cracknell cutting and pulling to good effect and he and De Caires passed 50 during the eighth over before the latter was pinned in front for Miller's maiden career wicket.

Cracknell (49 from 52) seemed to become bogged down as he neared what would have been his second half-century in as many games and feathered one behind off Broad, who then knocked back Sam Robson's off stump with his next delivery.

At 90 for three, Middlesex needed a substantial partnership and Stoneman took charge of his alliance with Fernandes, dominating the strike and pulling Raphy Weatherall crisply to the fence to reach his half-century at a run a ball.

While Stoneman found the boundary with regularity, the required rate escalated above eight an over and Middlesex hopes were dented when the captain chopped on to Broad with 100 still needed.

But Fernandes picked up the baton, launching Zaib for three consecutive fours before he was caught in the deep and Davies slammed 20 off Broad's final over before clipping Weatherall for another boundary to wrap up the win.