Steve Magoffin took five wickets before lunch to put Somerset on the ropes at Taunton but the hosts fought back to take the lead in their LV= County Championship Division One clash against Sussex.
The 34-year-old reduced Somerset to 39 for five, in response to 214, but half centuries from Craig Overton and Craig Kieswetter helped the home side to recover and take a 75-run first innings lead as they were all out for 289.
Magoffin, who has regularly terrorised Somerset since joining Sussex in 2012, added another wicket after lunch to take his overall haul against them to 36 in that time, but his total of six for 60 was not enough to stop the hosts from nudging in front.
Sussex finished on 26 without loss in their second innings to trail by 49 runs going into the third day.
At Edgbaston, Will Porterfield's unbeaten half-century provided a platform for Warwickshire as miserly bowling from Lancashire ensured it was slow going for them.
Warwickshire toiled through two sessions and 71 overs to reach 130 for four, which was positively pedestrian after Lancashire's tailenders had added 98 in less than two hours during the morning.
The home side finished 156 runs behind on 130 for four at stumps.
Yorkshire were frustrated by rain at Headingley on Monday with less than 10 overs possible as they looked to increase the pressure on Nottinghamshire.
The Tykes had dismissed their visitors for 205 on day one and resumed on 52 for two in the morning, bu t they could add only 24 to that total before the players were brought off due to bad light at 11.40am with Jack Leaning on 35 and skipper Andrew Gale on 23.
In Division Two, Rory Burns and Zafar Ansari shared an unbeaten opening stand of 186 as Surrey took complete control against Gloucestershire.
Matt Dunn took four for 37 while Jason Roy recorded career-best figures of three for nine from just four overs as Surrey dismissed their hosts for 112 before lunch.
Burns (98 not out) and Ansari (84 not out) then set about putting their team firmly in the driving seat, guiding them to 186 without loss at the close at Bristol, a lead of 74.
England all-rounder Ravi Bopara's 162 helped edge Essex into a slender first-innings lead as rain affected their match with Kent.
Mitchell Claydon took five wickets for Kent, but the visitors were dismissed for 440, which gave them a lead of 53.
By the close of play, Kent had reached 35 without loss from their hour back at the crease. Captain Robert Key was unbeaten on 17 and Daniel Bell-Drummond was 11 not out.
Rain also affected the match at the County Ground, but Ben Cox's maiden first-class hundred put Worcestershire in charge against Hampshire.
The 22-year-old chose the perfect time to move into three figures, helping his side put together a solid first-innings score of 402 for nine declared.
Hampshire were reduced to 10 for one by the close, with Michael Carberry going first ball, to leave them with a mountain to climb.