McLaren racing director Eric Boullier has calmed fears over the team's early performances in testing ahead of the new Formula One season.
During Tuesday's session in Barcelona, Stoffel Vandoorne completed just 38 laps amid a trio of mechanical failures and the picture was not much brighter 24 hours later.
Fernando Alonso suffered additional problems, although he did complete 57 circuits, before stopping two hours in due to what was identified as an oil leak.
Having struggled badly with Honda engines, accruing just 30 constructors' points last season, McLaren have switched to Renault for 2018.
Alonso did get back out for the final few minutes of testing on Wednesday and Boullier believes McLaren's early teething problems are to be expected.
"It's just testing," he said. "On the tyres, if you look at the lap time, Red Bull did a test this morning, [they] put on new mediums [and then] new softs.
"They are half a second faster only, so there is not much difference because of the tarmac specification and the temperature as well. We have a technical reason why we want to work on the car with these [hypersoft] tyres.
"[Regarding] the car breaking down, it's testing so we have some little issues which we have to fix, but it's just testing. It's part of the process. We are on top of this.
"It's a new partnership with Renault, completely new packaging for the car as well. This is testing. Give us time and it's fine."
Meanwhile, Red Bull and Mercedes continued to impress - Daniel Ricciardo setting an unofficial track record on hypersoft tyres, 0.353 seconds faster than defending champion Lewis Hamilton, who was running on ultrasofts.
|Casillas reaches 100 Champions League wins|
|Expansion franchise Cincinnati sign Garza, send Kamara to Rapids|
|Manchester City sign United States goalkeeper Steffen for reported £7m|
|Schalke 1 Lokomotiv Moscow 0: Russians miss chance for Europa League reprieve|
|Galatasaray 2 Porto 3: Terim´s men into Europa League after penalty drama|
|Jackman leaves Dragons role|
|Tottenham boosted as Barcelona bench Messi|
|Mane and Henderson in Liverpool XI to face Napoli|
|Mourinho shoots down question over how to get the best from Pogba|
|Ronaldo to start as Allegri aims to avoid Champions League big guns|
|Odriozola: I´m in love with Benzema, he´s the best number nine in the world|
|Vikings fire OC DeFilippo after loss to Seahawks|
|Marcelino suggests Valencia open to Batshuayi departure|
|Bottas to make rally debut in title-winning M-Sport Ford Fiesta|
|Kovac dismisses Pavard speculation|
|Yaya Toure leaves Olympiacos after just five appearances|
|Riise challenges Liverpool to banish Champions League disappointment against Napoli|
|We rallied around it - Durant on Green confrontation aftermath|
|Valencia ´p****d off´ with Fellaini´s controversial Young Boys winner - Soler|
|More must be done to combat racism at Premier League grounds – Chalobah|
|Napoli will not sack ´big signing´ Ancelotti if they miss Champions League qualification, says De La|
|Guardiola not interested in ´exceptional´ Saul|
|Shai gives Windies hope with thrilling ODI run chase|
|Ten Hag unsure whether to risk Ajax stars against Bayern|
|Erasmus to work with Bulls as Springboks assist Super Rugby sides|
|Paul Gascoigne pleads not guilty to sexual assault|
|Joshua is ´begging´ for unification fight, claims Wilder|
|Silva, Fernandinho add to Guardiola´s injury woes|
|Hosszu storms to 14th gold, Seto smashes Le Clos´ world record|
|Raheem is an incredible human being - Guardiola rallies behind City star Sterling|
|Sexton pens IRFU extension until 2021|
|Ajax boss Ten Hag can do big things, says Bayern chief Rummenigge|
|He´s good at basketball – Kerr running out of superlatives for Curry|
|Green thrilled to make Warriors return in victory over Timberwolves|
|Madrid squad great and humble - Solari responds to Ronaldo|
|Langer unsure what to expect from Perth wicket|
|Fournette subjected to alleged racial abuse in Titans loss - Marrone|
|Better and better - Mbappe hails Neymar link|
|It´s the end of one of the best movies you could ever see - James pays tribute to retiring Wade|
|NASA invites Curry to see moon rocks|
|No plan B for LaLiga Miami game after Barcelona withdrawal|
|Messi´s English haul, Neymar eyes hat-trick record - Champions League in Opta numbers|
|LeBron trumps Wade in last dance, Curry scores 38 points|
|Seahawks secure dominant win over Vikings|
|Iniesta visits Messi and former club Barcelona|
|Drake makes plea for ball thrown into stands after Miami miracle|
|´Toughest pretty boy I´ve ever met´ - Langer dismisses Paine concerns|
|Van Dijk says Liverpool can challenge for double ahead of Napoli decider|
|Hazard: I´ve always loved Real Madrid|
|Yankees interested in Machado, not Harper - Cashman|
|Warriors´ Curry believes moon landing was faked|
|76ers star Butler suffers strained groin|
|Brady: Patriots still have a lot of football to play|
|´No one died´ - Belichick´s message to Patriots after stunning loss|
|Silva lauds Digne after stunning free-kick|
|Aduriz joins Messi, Ramos in LaLiga history books|
|We have a plan - Ravens coach Harbaugh prepared for Flacco return|
|´It´s difficult to accept´ - Gracia calls for introduction of VAR|
|LaLiga press on with overseas match plan despite Barcelona withdrawal|
|PSG open Coupe de France defence at fifth-tier Pontivy|
|Hazard backs Sterling as Neville reveals England star´s Euro 2016 concerns|
|Everton 2 Watford 2: Digne salvages draw with 96th-minute free-kick|
|Barcelona could ´steal´ Kane, says Pochettino|
|Oakland Raiders fire general manager McKenzie|
|Struggling Villarreal appoint Garcia Plaza as Calleja successor|
|Warriors assign Cousins to G League team|
|Barcelona pull out of plan to play LaLiga game in Miami|
|Pochettino to keep an eye on Inter when Spurs face Barcelona|
|Pochettino confirms Walker-Peters set to start against Barcelona|
|Denver Nuggets add free agent Young|