Gloucestershire, who finished bottom of the Second Division last season, secured their first Championship victory since September 2007 after a tense finish at Wantage Road, where Northamptonshire fell 45 runs short of their target of 371.
They progressed to 321-8 at lunch after Andrew Hall and Steven Crook put on 65 for the seventh wicket before Hall was leg before to Alex Gidman. Northamptonshire's chance was lost after the interval when Crook was bowled by Jon Lewis for 55.
Durham sniffed a possible win at Taunton, after three wickets for the First Division champions in the morning session left Somerset four down and still 232 adrift, following on, despite Marcus Trescothick's hundred. But further centuries from their captain, Justin Langer, and a second of the season from wicketkeeper Craig Kieswetter in a stand of 197 for the fifth wicket, guided the home side to a draw. The same result looks inevitable at the Rose Bowl, where a century from England wicketkeeper Matt Prior on day three enabled Sussex to avoid the follow-on, but there is an outside chance of a result at Old Trafford, where Nottinghamshire go into the last day with a lead of 178. Kent, forced to follow on 165 behind, recovered well against Essex on day three at Chelmsford, where a century for Martin van Jaarsveld gave them a chance of setting a target on the last day.
Leicestershire's James Taylor, 19, made an unbeaten maiden century, helping his side reach 400-7 following on to salvage a draw against Middlesex at Southgate. Glamorgan bowled out Derbyshire for 210 and enforced the follow-on at Cardiff but that match, weather-hit, finished as a draw.