Derbyshire made a good start in their bid to end their long absence from the top flight of the LV= Championship at home to Hampshire.
The long-time Division Two leaders made the most of their decision to bowl first by reducing the visitors to 106 for four at lunch.
Tony Palladino led the way with three wickets for 18 runs in nine overs as Hampshire slipped to 59 for four before James Vince (48 not out) and Sean Ervine (16) staged a recovery.
Second-placed Yorkshire also made a strong start at Essex despite the early loss of Joe Root.
Adam Lyth's 67 at the top of the order laid a good foundation and when he departed with the score on 86, Phil Jaques (36no) guided his team to 111 for two at the interval.
Kent, in third, found the going slightly tougher against Glamorgan in Cardiff as the hosts reached 133 for two in the morning session.
William Bragg was the major contributor with 59 with Stewart Walters scoring an undefeated 39.
Shiv Thakor claimed two for 24 as Leicestershire reduced Gloucestershire to 121 for four at lunch.
The visitors could not get a partnership going until Hamish Marshall (31no) and Ian Cockbain (17no) put on an unbroken 50 for the fifth wicket.