Rosberg exposes Red Bull’s biggest weakness against Mercedes

Nico Rosberg believes the key difference between Mercedes and Red Bull-Ford power units isn't the internal combustion engine, but battery efficiency — an area where Mercedes excels. Red Bull built the fastest ICE from scratch, yet its energy management remains the weak point.

Why it matters:

The power unit battle is shaping the 2026 season. Red Bull’s engine was declared the benchmark in the first two FIA evaluation thresholds, meaning it received no extra development tokens. But Mercedes has quietly compensated with superior battery efficiency, keeping the title fight tight.

The details:

• Red Bull’s strength: Despite starting from zero, Red Bull-Ford produced the most powerful combustion engine on the grid. Rosberg called that achievement “incredible.”
• Mercedes’ edge: The Mercedes ICE is down about 2% on power compared to Red Bull’s, but its battery efficiency is so strong that it levels the playing field. Rosberg says that’s where Red Bull needs to make progress.
• Development freeze: Mercedes has paused upgrades since Canada, where it brought a large package. The team will resume W17 development in Malaysia in early October.
• Baku expectations: Mercedes won’t bring major new parts to Baku, focusing instead on low drag and straight-line performance.

What's next:

Rosberg is convinced Red Bull can close the gap quickly, potentially challenging for race wins before the end of the season. Mercedes, meanwhile, is preparing a fresh upgrade push in October — setting up a key stretch run in the development race.