Martin Brundle described the W14 as the 'worst car' through part of the final sector during FP2 as the teams collected data for Sunday's Hungarian Grand Prix.
The team demonstrated some pace in the wet weather conditions experienced in FP1, but it was a totally different story in FP2.
When the chequered flag waved on the session, Lewis Hamilton was sitting way down in P16 with George Russell bottom of the running order in P20.
This was a stark contrast to Mercedes' experience at the Hungaroring this time last year, where the team returned to the podium in style and kickstarted the revival of the season.
Mercedes struggling for pace
During FP2 ahead of the Hungarian Grand Prix, Sky Sports F1 co-commentator Martin Brundle headed trackside to take a better look at the cars at various points across the circuit.
Standing at the exit of the penultimate corner, the veteran broadcaster was unimpressed by the handling of the Mercedes car.
Speaking during the FP2 broadcast, Brundle explained: "I would say actually, just about the worst car I’ve seen coming through here is the Mercedes.
Brundle then detailed how much hassle the car was giving Hamilton and Russell as they wrestled the W14 through the twisty final sector.
"Both Mercedes drivers really having to work the steering wheel to keep the car on line," Brundle continued. "And to get some kind of traction."