Durham won the toss and elected to bat first on a very green wicket in extremely hot and humid conditions.
Graham Onions opened the Durham attack and struck third ball when Paul Horton was trapped lbw with runs yet to be added to the board.
Karl Brown added five runs before he became the first of three consecutive wickets to be caught behind by skipper Phil Mustard off the bowling of Callum Thorp. With swing impacting on their progress having lost Mark Chilton and Steven Croft in the 12th and 18th overs, Lancashire slumped to 37-4.
Lancashire lost another two quick wickets just after they passed the fifty mark with Luke Procter trapped lbw by Dale Benkenstein for 5 in the 24th over.
Stephen Moore, one of only two Lancashire players to reach double figures in the innings, was caught behind for 27 off Stephen Harmison in his sixth over as Lancashire fell to 54-6.
Thorp claimed his fourth scalp in the fourth wicket after lunch with Gareth Cross caught by Paul Collingwood at first slip for 8.
Onions caught Sajid Mahmood off his bowling for 14 the following over and then Thorp, continuing to swing the ball
nicely claimed the wicket of xx Khan on his first class debut, who nicked the ball to Michael Di Venuto at second slip without scoring.
Thorp claimed the final wicket, bowling Kyle Hogg for 1, dismissing Lancashire for 84 and ending the innings with figures of 6-20 off his 12.2 overs.
During the lunch break conditions did change with more cloud covering and a drop in temperature occurring. The ECB pitch inspector, who was here on a pre- scheduled visit, indicated that despite the loss of wickets he was happy with the pitch.
The Durham innings started along on a similar pattern to that of Lancashire losing two early wickets, those of openers Will Smith, who was trapped lbw by Hogg’s third delivery, and Michael Di Venuto, who fell to the same fate in the bowlers subsequent over as Durham fell to 8-2.
Gordon Muchall and Paul Collingwood added thirty before the latter was caught by Keedy at mid on, off Mahmood for 11.
Muchall, who was caught behind off Khan for 28, fell just after Durham reached the fifty mark bringing Ian Blackwell to the middle, who was bowled six deliveries later by Mahmood for 1 with Durham 55-5 in the 18th over.
Mahmood claimed his third wicket, that of Phil Mustard (6) who was trapped lbw, in the 20th over.
A 41 run partnership from Dale Benkenstein and Scott Borthwick steadied the Durham innings and saw the visitors pass the hosts total but Procter added further pressure by dismissing the young spinner for 13 and his replacement in the middle, Callum Thorp, first ball with Durham 102-8.
By tea Durham had achieved a lead of 30 with the dependable Benkenstein, batting with caution and with great support from Onions, to reach his fifty, which included six fours, off 88 balls as Durham reached 141-8 in the 38th over.
Procter eventually had Onions nick the ball to the slips after contributing 21 from his 89 minutes in the middle, bringing the vital 79 run partnership to an end.
Harmison was bowled by Keedy without scoring with Durham posting a first innings total of 186, having established a lead of 102.
Lancashire took to the field with eight overs of the day remaining but only three deliveries were made before play was abandoned for the evening due to bad light.
Durhamccc.co.uk caught up with Callum Thorp at the close, ““The pitch offered a bit early like any first day pitch but it swung around all day so that was quite enjoyable for me. We did some research on the way down that gave us an idea of what it does down here first day and we knew if we won the toss we wanted to bowl, and we did.
“For me, the break for the t20 has been nice, my legs were starting to hurt a bit after so many games in the first two months but it’s been tough for those guys that have had to push through and play in all competitions.
“I’ve not played in a lot of games where 20 wickets have fallen in a day, maybe in club cricket, but not first class, it’s very rare! I think Benki’s innings really stood out, it was a phenomenal innings to score runs on that wicket because it was swinging round corners still, it was awesome from him.
“On the stats we’ve looked at it has looked at it looks as though the pitches here do settle down a bit over the days so we’ll have to bow well tomorrow and keep it tight.
“Lancashire are still our main rivals, they still have a game in hand so the points here are vital.”