Middlesex, with one first-innings wicket in hand, lead Surrey by 225 runs after the first day’s play at Lord’s.
They struggled to contend with the variation and skill of Jade Dernbach, who was in fine form again.
Dernbach has become a key player for England’s one-day side and Sussex were powerless against him in Surrey’s opening County Championship first division victory at the Oval last week.
Top-order batsmen Chris Rogers, captain Neil Dexter and wicketkeeper John Simpson all fell to Dernbach in a dangerous second session spell, and the youngster was on for a hat-trick in the 35th over having taken Dexter (1) and Simpson (0) in back-to-back deliveries.
But Middlesex number four Dawid Malan went on to grab a half-century and remained 65 unbeaten at the close with the score at 225-9.
Surrey won the toss and elected to put Middlesex into bat under gloomy skies with intermittent sunshine through the day, and bad light delayed play after 57 overs.
Dernbach’s opening wicket, catching Rogers lbw with a quicker delivery for 20 runs, was made after openers Sam Robson (40) and Joe Denly (10) had made a short 33-run partnership from the opening 10 overs.
Denly had the furniture toppled from behind him by Jon Lewis, who took figures of 2-45 himself from the day.
Rogers’ wicket made it 66-2 from 21.3 overs before Dernbach grabbed his second and third in quick succession, but Malan and Gareth Berg took Middlesex’s tally over the hundred mark with the foundations of a good partnership.
But Berg (11) became Tim Linley’s second wicket after 40 overs and Ollie Rayner followed after 48 overs with Middlesex at 129-7.