Ross Brawn has admitted his Mercedes team have “got a bit of work to do” in order to catch McLaren and Ferrari while Michael Schumacher says he does not expect to challenge for early-season race wins.

Though wary of drawing firm conclusions from the opening three days of winter testing, Brawn all-but conceded that his team are lagging behind the pace-setters despite Schumacher’s return.

“It’s always very difficult to judge. On full tanks on Tuesday we didn’t look too bad but we’re a little bit off on pace and [there are problems with] the handling and balance of the car which we can fix for Jerez. We know what the problem is,” Brawn told the BBC.

“Of course the other teams will be progressing as well so we are reasonable, not as quick as Ferrari and Lewis looked quick yesterday. So it looks like we’ve got a bit of work to do.”

Schumacher’s running on Wednesday was brought to a premature conclusion due to a hydraulic fault. The German finished the day a second down on Fernando Alonso.

Speaking to Autosport, Schumacher, making his comeback after three years of inactivity, offered a more positive assessment of the team’s position – though he also accepted that Ferrari are currently out in front and it may be a while before Mercedes close the gap.

“The car is running very smoothly, very nicely. I’m very positive,” he reported. “I’m thinking we will be competitive, but whether this is a winning car straightaway or not, that’s another story. For me that’s not so important – it’s a long season. We need to be there and taking points from the beginning.

“I wouldn’t expect to be winning right from the beginning. It wasn’t something that I was aiming for and expecting to be the case. But we need to be strong enough on development.”

But Schumacher was also able to report that, on a personal level, his comeback had gone smoothly.

“Actually it’s been much easier than I anticipated,” he announced. “I thought it would need a bit more time but it went pretty quickly. I’m really happy.”