Curran took 4-61, whilst Stuart Meaker claimed three victims as Jordan Clark top-scored for Lancs with 56 of their 287 all-out total. Surrey reached 50-0 at the close, 237 behind with all ten wickets still in hand.
After turning down the option to bowl first, Lancashire won the toss and batted as the Curran brothers took the new ball and proceeded to make a breakthrough just seven overs into the day.
Sam Curran trapped Luke Procter in front for five to leave the visitors 15-1 and Liam Livingstone joined the in-form Haseeb Hameed.
Lancashire found it hard going at The Oval, taking more than 20 overs to bring the 50 up and then immediately losing Hameed as Meaker joined forces with Ben Foakes for the first time in the innings as the wicket-keeper took a smart leg side catch behind the stumps.
The pressure was continuously applied by Surrey’s bowlers as Sam Curran struck again eight overs later to remove the dangerous Alviro Petersen for 17 – he played on trying to leave the ball.
This prompted a period of further strife for the northern visitors as three wickets fell for just 18 runs as Livingstone went to Tom Curran for a gritty 37, giving Foakes his second catch of the day.
Lancashire weren’t to score another run before Steven Croft became Sam Curran’s third scalp – as well as Foakes’ as he became the third man to be caught behind.
Debutant Rob Jones paired up with Clark and the two of them led a solid but modest counter-attack, hitting 85 from the next 25 overs until Sam Curran and Meaker struck again.
The two set batsmen were both removed in the space of three overs after Kumar Sangakkara took a fantastic one-handed diving catch to his right to see the back of Clark for a 75-ball 56 and then Jones dragged Sam Curran on for a solid 25 on debut.
That brought Curran’s 4-61 from 17 overs to a close and left Lancashire with an uncertain future on 198-7. Arron Lilley wasn’t hanging about though and attempted some heroics – uppercutting Meaker for six before hitting a drive over cover for the same just before tea.
He was to hit two more sixes after tea to move to 35 before Kyle Jarvis – with whom he had added 33 runs in five overs – was the other Curran brother’s second wicket of the day (that’s Tom by the way).
Lilley scored just three more runs after Jarvis’ wicket as he edged a short ball from Meaker through to Foakes for 38 from 28. The Surrey bowler had chalked up 3-83 from 20 overs.
Mark Footitt got himself on the board at last after Lancs’ final pair of Nathan Buck and Simon Kerrigan had frustrated the home team and put on 48 in nine overs for the final wicket, Kerrigan struck a brisk 25 from 27 before he was caught behind, giving Foakes his fifth catch of the innings.
Buck was left stranded on 24 but the pair had given Lancashire a fairly competitive score and took Lancashire to 287 all out after being 99-5.
Surrey had 15 overs to bat out after taking just 78 overs to bowl out Lancashire. That gave Rory Burns just enough time to register 1,000 Championship runs for the season.
It was undoubtedly the host side’s day as they reached the close of play on 50-0 from their 15 overs; Burns unbeaten on 33 and fellow opener Dominic Sibley ten not out overnight.
