Somerset pair Lewis Gregory and Craig Overton shared nine wickets as the MCC gained the upper hand against Middlesex on day two in Abu Dhabi.
Resuming on nine for one in reply to the MCC's first-innings 332 all out, the county champions were reliant on a half-century from Dawid Malan to reach 179.
With a 153-run first-innings deficit, Middlesex then fought back with the ball as Harry Podmore took three wickets to reduce the MCC to 145 for seven - a lead of 298.
Rather than new-ball pair Gregory and Overton, it was Somerset spinner Jack Leach who made the initial breakthrough in the morning by bowling Tom Helm for 15.
The seamers then took over, with Gregory bowling Nick Compton, having Nick Gubbins held in the slips and Stevie Eskinazi caught behind to reduce Middlesex to 68 for five.
Malan and John Simpson shared a 96-run stand for the sixth wicket, but when left-hander Malan was trapped lbw by Overton, the last four wickets added just 15 runs.
Gregory completed figures of five for 32, while Overton had four for 37 and will start the second innings on a hat-trick after dismissing Podmore and Ravi Patel with successive deliveries to bring the innings to a close.
Adam Lyth added 42 in the MCC's second innings but there was precious little support as Podmore's three for 25 reduced them to 100 for six, only for Gregory (32) and Overton to share a 40-run stand before the former was bowled by Helm late in the day.
The MCC will be without Liam Plunkett for the rest of the match after the England and Yorkshire paceman suffered a minor calf injury.
Source: PA
