Yorkshire and Nottinghamshire joined the non-playing Surrey on 36 points with a comprehensive wins.
Yorkshire, putting their championship and NatWest woes behind them, beat Gloucestershire by 133 runs and Nottinghamshire defeated Derbyshire by eight wickets.
In Yorkshire's 262 for 7 David Byas hit 56, and Martyn Moxon and Michael Vaughan reached the forties but the acceleration came from Peter Hartley. His Sunday-best 52 came from 29 balls, with four sixes.
Gloucestershire made little progress with Craig White taking three wickets and Richard Stemp four as the home side were bowled out for 129.
Nottinghamshire's chase of 230 proved surprisingly easy, reached with 3.1 overs remaining. Tim Robinson and Mathew Dowman put on 87 for the first-wicket, Robinson and Paul Johnson added the same before the opener fell for 90 with the captain eventually unbeaten on 71.
England's newcomer, Robert Croft, tried his best for Glamorgan but they were easily beaten by Warwickshire at Edgbaston. The 26-year-old off- spinner scored 23 out of 128 and then took 1 for 15 in eight overs. Warwickshire had few problems chasing such a small total and with Nick Knight making an unbeaten 73 as they won by seven wickets.Reuse content