McLaren Formula 1 team racing director Eric Boullier believes the clutch issue that blighted the squad's Bahrain Grand Prix has been resolved and will not be repeated.
Both McLaren drivers succumbed to clutch trouble in last weekend's race, with Kevin Magnussen retiring on lap 40 before Jenson Button - who felt he was on course for a fifth-placed finish - followed suit on the penultimate lap.
Boullier suggested that the cause of the problem has been diagnosed and eradicated in the intervening days between the race and this week's two-day test session in Bahrain.
"It was a one-off," he said.
"It has been fixed on the cars and as you have seen today and yesterday [in Bahrain], it is gone already.
"It was a dilemma at the time and was obviously a concern because we had two DNFs, but the matter is now fixed."
Boullier also agreed with Button's assertion that McLaren is currently second quickest behind Mercedes and reckons it can catch its Brackley-based rival in the near future.
"If you look at the performance from Jenson, we were potentially going to finish in front of the Force Indias," he said.
"So I agree that we could have been the best of the rest.
"We need to aggressively look to see if we can catch up with [Mercedes] and we will know if we are doing so within a few races, but we will try to close the gap to them as quickly as possible.
"The gap is huge, but a one-second gap is catchable.
"I know areas where we can work on and ways we can improve, so I say Mercedes is definitely catchable."
Subscribe to Autosport Plus
Register for free