Carlos Sainz Alerts Williams To Deep Rooted Performance Deficits Beyond Ongoing FW48 Weight Reduction Struggles

Carlos Sainz claims Williams needs major performance upgrades to exit Q1, noting the Mercedes power unit is the only part of the FW48 currently delivering.

By: AXL Media

Published: Mar 14, 2026, 4:24 PM EDT

Source: Information for this report was sourced from PlanetF1

Stagnation At The Back Of The Grid Sparks Internal Alarm

Carlos Sainz provided a sobering assessment of Williams’ current technical state, suggesting that the team’s problems extend far beyond the well documented issues with the FW48’s chassis weight. After failing to advance past the first round of qualifying in Shanghai, the four time race winner noted that the car currently lacks the fundamental pace required to compete in the midfield. Despite high expectations following a successful previous season, the team remains one of the few yet to score a point, a situation Sainz believes will make for a very long year if immediate developmental steps are not taken to unlock dormant performance.

Mercedes Power Unit Remains Lone Bright Spot In Technical Package

In a rare moment of praise amidst the technical criticism, Sainz highlighted the Mercedes power unit as the only component of the car performing at a championship level. He observed that the engine consistently ranks at the top of the timing sheets across various sessions, proving that the deficit lies entirely within the Williams chassis and aerodynamic philosophy. While refinements in engine mapping have been made since the season opener in Australia, Sainz emphasized that the primary weaknesses of the car are mechanical in nature, leaving the superior horsepower of the Mercedes unit unable to compensate for the lack of cornering speed.

Missing Pre Season Milestones Casts Long Shadow Over 2026

The current lack of competitiveness is being traced back to a troubled winter period where Williams famously missed its initial shakedown test. This developmental delay has forced the team to spend the opening rounds of the season in a reactive state, playing catch up while rivals have already begun iterating on their launch packages. For Sainz, the struggle in China is a direct continuation of the difficulties faced in Melbourne, where his track time was severely limited by reliability and setup hurdles. The Spaniard noted that the team is effectively biding its time, waiting for a major update package that has yet to materialize.