McLaren's woeful pre-season continued on the final day of the Barcelona test as Fernando Alonso's MCL32 twice ground to a halt at the Circuit de Catalunya.

The former world champion's team and engine suppliers Honda have been plagued by problems which showed no signs of improving, with the first race of the season in Australia just over two weeks away.

Alonso's car stopped twice on the track on Friday's morning session to add to the two red flags on Thursday as the team were again robbed of valuable track time ahead of the Melbourne race.

The first stoppage came just over halfway into the morning session, with Alonso's car eventually taking its now customary place on the back of the recovery truck after a short break.

The 2017 Formula 1 grid Show all 20 1 /20 The 2017 Formula 1 grid The 2017 Formula 1 grid Sebastian Vettel, Ferrari Vettel finished fourth last season and will hope improvements to the team's 1.6-litre V6 will help him back onto the podium. Getty The 2017 Formula 1 grid Kimi Raikkonen, Ferrari The experienced Finn largely underperformed last season. At 37, could be his final season racing for a top team. Getty The 2017 Formula 1 grid Sergio Perez, Force India Perez retains the drive he has held since 2014. Force India again use the Mercedes-AMG engine. Getty The 2017 Formula 1 grid Esteban Ocon, Force India The talented 20-year-old raced in 9 Grand Prix for Manor last season and earns a call-up to a much more competitive team. Getty The 2017 Formula 1 grid Romain Grosjean, Haas Haas had a very good season last year, finishing 8th with their Ferrari engine. Grosjean will look to improve on his 13th place finish. AFP/Getty The 2017 Formula 1 grid Kevin Magnussen, Haas The Dane moves from Renault to Haas. Struggled last season. Getty The 2017 Formula 1 grid Stoffel Vandoorne, McLaren The talented Belgian, who scored a world championship point in the unfamiliar MP4-31 last year, replaces Jenson Button at McLaren. Getty The 2017 Formula 1 grid Fernando Alonso, McLaren The youngest double champion of all-time remains at McLaren for the 2017 season, despite a well publicised approach from Mercedes. Getty The 2017 Formula 1 grid Lewis Hamilton, Mercedes The team - and driver - to beat since the infamous V6 rule changes came into place in 2014. Getty The 2017 Formula 1 grid Valtteri Bottas, Mercedes Bottas replaces world champion Nico Rosberg at Mercedes, Will push Hamilton all the way this campaign. Getty The 2017 Formula 1 grid Daniel Ricciardo, Red Bull Adrian Newey has completely redesigned the RB13 for the 2017 season and Ricciardo will be hopeful of bettering last year's 3rd place finish. Getty The 2017 Formula 1 grid Max Verstappen, Red Bull There will be plenty of attention on Verstappen as he completes his first full season at Red Bull. Getty The 2017 Formula 1 grid Nico Hulkenberg, Renault Hulkenberg moves to the team from Force India, replacing Kevin Magnussen. Getty The 2017 Formula 1 grid Jolyon Palmer, Renault The Brit came under pressure last year for a disappointing 18th-place finish. Will be hopeful of improvement. Getty The 2017 Formula 1 grid Marcus Ericsson, Sauber Sauber were poor last season and were plagued by retirements. Ericsson nevertheless remains with the team for a third campaign. AFP/Getty The 2017 Formula 1 grid Pascal Wehrlein, Sauber The 22-year-old wins a drive at Sauber, moving from Manor Racing. Getty The 2017 Formula 1 grid Daniil Kvyat, Toro Rosso Resigned to Toro Rosso after plenty of speculation; will be desperate to show he shouldn't have been replaced by Verstappen at Red Bull. Getty The 2017 Formula 1 grid Carlos Sainz Jr, Toro Rosso Now in his third season with the team. Toro Rosso this year return to a Renault engine. Getty The 2017 Formula 1 grid Lance Stroll, Williams 18-year-old rookie. Stroll's first appearance in the car didn't inspire confidence, he spun the car in testing. Getty The 2017 Formula 1 grid Felipe Massa, Williams Heroically returns to the team after Bottas departed for Mercedes. One of the most experienced drivers on the grid. Getty

But when the Spaniard returned to the track with a little over an hour of the session left it stopped again almost straight away.

The double world champion had blamed McLaren's woes on engine supplier Honda earlier in the week, and the Japanese manufacturer admitted his Friday setbacks were caused by the same electrical problem which hit team-mate Stoffel Vandoorne on Thursday.

A Honda spokesperson said: "Fernando has stopped out on track with the same issue that Stoffel encountered yesterday - intermittent electrical shutdown.

"Various electrical components in the PU and chassis were changed overnight, and the team are making further changes to eliminate variables and identify the source of the problem."

Alonso returned to the track with just over two hours of testing remaining, with his team posting on Twitter: "After encountering another electrical issue, we carried out several fixes to the car. Our afternoon run plan now resumes."

Former world champion Sebastian Vettel had set the best time of testing so far on Thursday with a lap of one minute 19.024 seconds, but on Friday morning he was usurped by Ferrari team-mate Kimi Raikkonen.

The Finn posted a best time of 1:18.634 to top the morning session, but had concentrated on race simulations after lunch before his Ferrari broke down in the chicane.

Second quickest in the morning was Red Bull's Max Verstappen in 1:19.438, but his afternoon track time was restricted as his team battled with an issue with the car's turbocharger.

Carlos Sainz set a surprise third best time in the morning in the Toro Rosso and he lowered that to 1:19.837 before he too encountered problems and stopped on track late in the afternoon.

Romain Grosjean had an eventful morning session as he lost the rear end of his Haas and ended up in the gravel and later stopped on the back straight, his two red flags sandwiching those of Alonso.

New Mercedes driver Valtteri Bottas' 1:19.845 was good enough for fourth ahead of his team-mate Lewis Hamilton, who took over duties after lunch, the Renault of Nico Hulkenburg and Force India's Sergio Perez.

Jolyon Palmer was making the most of Renault solving their reliability issues to post the eighth best time ahead of Canadian Lance Stroll, the Formula 3 champion putting his recent crash spree behind him to clock up over 100 laps for Williams.