Red Bull is emerging as a potential favourite for the 2018 world championship.
After Mercedes' Toto Wolff said on Tuesday that Red Bull is leading the testing pack, Daniel Ricciardo smashed the Barcelona circuit record on day two of the final winter test.
"It's very close between Ferrari, Red Bull and us," Mercedes team chairman Niki Lauda agreed in conversation with Auto Motor und Sport.
"Right now it looks like a head-to-head between Red Bull and us. We don't know about Ferrari yet, but going by Wednesday they are a little behind," he added.
Australian Ricciardo thinks Mercedes still has the edge over Red Bull.
"I'm not sure about Ferrari, but I think Mercedes still look very fast," he said. "But at least we're not a second behind like last year."
Some British bookies are showing Ricciardo with odds of 10-1 for the championship.
The Australian smiled: "I'm not a big gambler but if one of my friends is watching, then I'd say put a cheeky $75 000 on it."
As for the battle behind the big three, Renault appears to be leading the pack.
"Toro Rosso looks a bit better than expected, and Force India a little worse," said Williams' Rob Smedley. "We are in the middle, roughly at the level of Haas."
