Toto Wolff says it is "crucial" for the development of Mercedes' 2027 car that they understand the full extent of their recent upgrade's potential after a "step in the right direction" at the Singapore Grand Prix.

Mercedes took what Wolff admitted was the "unusual" step of running two different car specifications at the last race after troubles with the big car upgrade introduced onto both W17s at the previous round in Malaysia, the world championship leader's first major upgrade since May.

Kimi Antonelli ran the newer spec in Singapore, while George Russell reverted to the older package on a weekend he already knew he would start at the back of the Grand Prix grid owing to engine penalties.

Russell with the older package proved the quicker of the two drivers in the initial Sprint sessions before Antonelli, with the newer package, was then faster in main qualifying before finishing third in the Grand Prix, moving a significant step closer to winning the world title.

Antonelli expressed confidence afterwards that "we started to see the light at the end of the tunnel".

Reflecting on the split programme at the end of the weekend, Mercedes team principal Wolff said: "We made the unusual move in a cutting-edge technology business to have two different cars because we felt we need to accelerate our learning curve and that was good.

"Fundamentally, looking back at the race, I think that this new car needs a very different set-up philosophy than the previous car. This is what we're learning at the moment.

"Was it an easy car like the previous one? I don't think it was. Does it have the performance that we were hoping the upgrade would bring? I don't think so yet. But it was a step in the right direction.

"In Austin, we should see whether we can continue to consolidate that and whether it has more performance because it's crucial for the development direction for the next year."

Mercedes also added a new front wing to package on Antonelli's car at the start of the Singapore Sprint weekend, although this was taken off after the sole practice session.

Mercedes likely to run both cars with latest package in Austin

Wolff added that he expected that both cars would run the newer specification at next week's United States Grand Prix, pending a final decision by the team before Austin.

"The latest is that we probably want to run the new cars in Austin," he said.

"Both drivers think it should have a positive effect, or it should have a benefit, in Austin, and I think in terms of us learning for next year this is the right direction to go.

"Again, I'm saying before the clever groups have come together tomorrow [on Monday after the race] and after tomorrow, we'll see what the next iteration will be we want to go."