Somerset 152 and 112-5 trail Middlesex 347 by 83 runs
Tim Murtagh led a stunning bowling display as Middlesex took 15 wickets in a day to put them on the verge of a convincing victory.
On a remarkable second day at Taunton, Somerset were bowled out for 152 and then reduced to 35-5 following on.
Murtagh, who also hit a quickfire 29 at the start of the day, took four wickets in both innings but Toby Roland-Jones, James Harris, Neil Dexter and Gareth Berg all chipped in.
Joss Buttler and Peter Trego staged a fightback in the second innings to leave the home side on 112-5 at the close – but they are still 83 runs short of making Middlesex bat again.
Earlier, Dexter was dismissed for 82 as Middlesex added 54 to their overnight score before being dismissed for 347.
That total now appears more than enough to win the match after a remarkable spell of bowling on Thursday.
Middlesex resumed on 293-8 and picked up the third batting bonus point before Dexter was removed by Jamie Overton inside the first half hour.
Murtagh’s 29 from 24 balls, which including four fours, added a final flourish until he was bowled by Overton, who finished with 6-95.
In reply, former England opener Marcus Trescothick made a brisk start with 24 from 28 balls.
But Murtagh took two wickets in as many balls, inducing an edge behind from Trescothick before claiming Alviro Petersen first ball.
Harris bowled Arul Suppiah for his first Middlesex wicket in the last over before lunch and Murtagh then accounted for Lewis Gregory and James Hildreth in the first hour after lunch to leave Somerset on 84-5.
Roland-Jones got in on the act with the wickets of Joss Buttler for 15 and Jack Leach for 1 while Alfonso Thomas fell to Gareth Berg.
Dexter took the last two wickets, including that of top scorer Peter Trego (34), and Middlesex skipper Chris Rogers had no hesitation in putting Somerset in again.
Middlesex were in the same position against Surrey two weeks ago but dug themselves out with a magnificent batting performance in their second innings.
This time, however, there was no similar rearguard from Somerset, who crumbled from the moment opener Suppiah was out first ball to Murtagh.
Petersen and Trescothick also went cheaply and the relentless Murtagh took the wickets of Hildreth and Gregory as Middlesex started dreaming of a win inside two days.
However, Buttler (20 not out) and Trego (58 not out) hit back with 11 fours between them in an unbroken stand of 77 which saw a relieved Somerset through to the close.
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This post was last modified on 17/05/2013