|LV County Championship Division One, Liverpool|
|Close of play, day one: Lancashire 84 & 4-0, Durham 186|
|Lancashire 3pts, Durham 3pts|
Durham's Callum Thorp took centre stage as 20 wickets fell on a steamy day of swing against Lancashire at Aigburth.
Graham Onions (2-19) backed up Thorp's 6-20 as Lancashire were shot out by Durham's pace attack before lunch for just 84 in the battle of the top two.
The home side hit back to reduce Durham to 61-6, only for Dale Benkenstein (83no) and Onions (21) to salvage a post-tea recovery to 186 all out.
Lancashire then reached 4-0 before an early close, still 98 runs adrift.
Despite ball dominating for large parts of a swinging, action-packed day at Aigburth, during which Lancashire posted their lowest score since making 51 against Glamorgan here in 1997, the quality of the track was not called into question.
The metronomic Thorp snared Karl Brown, Mark Chilton and Steven Croft, Gareth Cross, Kyle Hogg and debutant Junaid Khan, three of them caught behind by visiting skipper Phil Mustard, who claimed four scalps.
And there were good efforts in the Lancashire pace attack from Kyle Hogg, Saj Mahmood, who took 10 wickets in last week's win against champions Nottinghamshire, and Luke Procter (3-39).
But England and Wales Cricket Board pitch liaison officer Peter Walker described it as "as good a pitch as I've ever seen".
Benkenstein showed that when he and Onions put on 79 for the ninth wicket in the final session.
Having hit a hundred to help Durham beat Lancashire at Chester-le-Street earlier this month, Benkenstein did even more to infuriate home supporters with a 83 not out, hitting 10 fours in his 133-ball stay at the crease.
By contrast, only two Lancashire batsmen reached double figures, Stephen Moore top scoring with 27 as Thorp and Onions took advantage of movement off the pitch and through the air.
And Lancashire's total would have been even lower but for their next top scorer, Steve Harmison, who conceded 16 runs in wides, three of which went all the way to the boundary.
But, when Moore and fellow opener Paul Horton returned to the crease for the second time in the day, they had no time to make amends.
Horton faced just three balls before bad light called an early haly with eight overs still to be faced.
CLOSE OF PLAY SUMMARY
BBC Radio 5 live's Kevin Howells:
"Without doubt Callum Thorp bowled really well. Take nothing away from his deserved figures 6-20 with a swinging ball. However 18 wickets falling before tea was not what we were looking for in such a big game.
"The batsman might lay the blame on the farcical schedule of Twenty20 cricket mixed in with the serious stuff. Different day, different city, different skills.
"What it does show is the talent of Dale Benkenstein being mentally able to adapt so well and quickly to whatever challenge he faces."