Former Aussie international Dan Worrall has helped Surrey keep a stranglehold on Durham by taking four wickets - including three in three overs - in their English County Championship clash at London's Oval.
Responding to Surrey's club record 9-820 , Durham captain Alex Lees posted 125 before being dismissed by the Melbourne-born Worrall, whose 4-49 also included the scalp of Ollie Robinson for 79.
Matthew Fisher chipped in with 3-69 as Durham reached stumps on 9-343, trailing by 477 runs.
There was also an Australian influence in the second division encounter between Lancashire and Derbyshire at Chesterfield.
Aussie batter Aston Turner smashed an unbeaten 121 for Lancashire, with George Balderson contributing a rapid-fire 82 before they declared on 6-406.
Derbyshire's chase got off to a tricky start when James Anderson struck in the fifth over to dismiss Australian opener Caleb Jewell for nine and they closed on 3-139 with captain Wayne Madsen unbeaten on 39.
Leicestershire were defeated for the first time in the championship this season after losing by an innings and 127 runs to Middlesex.
The Division Two leaders were bowled out for 205 in the first innings, Naavya Sharma's 4-43 having done the damage, and Middlesex enforced the follow-on.
Noah Cornwell then took 3-60 in the second innings, including the final wicket of Sam Wood to end the match, as Leicestershire tumbled to 202 all out with Logan van Beek's unbeaten 36 their top score.
Back in the top flight, Worcestershire took complete control of their encounter with Hampshire, forcing their opponents to follow on and ending the day with a 372-run lead.
Replying to 7-679 declared, Hampshire were bowled out for 221 with Tom Taylor taking 4-42 and Tilak Varma top-scoring with 56.
They then fell to 3-86 in their second innings after Adam Finch took 2-5 in eight overs.
Centuries from Ben Slater and Jack Haynes helped Nottinghamshire take a 126-run lead over Somerset.
Slater was dismissed early for 124 by Jack Leach, who claimed six wickets overall - including Ishan Kishan for 77 and Lyndon James for 66.
Haynes starred with 157 off 295 balls before being trapped lbw by Leach as Nottinghamshire were all out for 509.
Liam Patterson-White removed nightwatchman opener Matt Henry to end the one over so far of Somerset's second innings.