Renault's technical bosses have admitted that the team must rapidly regain ground to prevent Fernando Alonso regretting his decision to return to the squad.
Alonso got his second Renault stint off to a strong start with a charging fourth place in Australia, but he could only manage eighth at Sepang and 10th at Sakhir.
Amid rumours that the former world champion could be snapped up by Ferrari next season, Renault's technical director Bob Bell said the team had to prove itself again.
"I think he's very disappointed, and rightly so, that we haven't delivered the car he expected to get," said Bell in Renault's official team podcast.
"He wasn't under any illusions that we were going to be back fighting for the championship with Ferrari.
"I think his expectations were much more in line with the team's hope and belief that we would be up there fighting for podiums and when other people dropped off we could be there to snatch victory.
"He came in with that same level of expectation and we haven't met that.
"But he is a real fighter.
"It doesn't matter what equipment we give him or what circumstances he finds himself in, he extracts the most from the car.
"That determination and drive is still there.
"We need to keep that alive by making sure that we do address the problems with the car as quickly as we possibly can and show him real performance improvement.
"If we do that – and it's certainly the plan – he'll be fine."
Pat Symonds, Renault's executive director of engineering, agreed that Alonso was currently over-achieving for the team.
"I think Fernando's qualifying performance probably flattered us a little," he said.
"We were not the 10th-fastest car out there, we were more like 12th, 13th as the fastest laps suggest."
Renault is set to introduce a number of upgrades for Alonso's home race at Catalunya later this month, but Bell said this would just be an initial step.
"To say we need to improve is an understatement – it will take a tidal wave of change, but that's what we're here to do," he said.
"We need to take the first step in Barcelona: we need to clearly demonstrate there that we've made a step forward as we start to move ourselves back towards the leading three teams and edge ourselves away from that gaggle of teams sitting just behind them.
"That's objective number one, and then by mid-season we really need to have shown that we have consolidated and we are back there on the tails of the top teams."