MANAMA -  Fernando Alonso 's outburst of frustration and Stoffel Vandoorne's mid-race tweeted photograph summed up McLaren's failures in Sunday's Bahrain Grand Prix and hinted at deeper turmoil ahead.

The Spanish two-time champion said he had never raced with so little power in his life while Belgian new boy Vandoorne posted a picture of him running on a treadmill after another engine failure had prevented him starting. Both men's action underlined the problems at McLaren where a promising chassis has been unable to show its real potential because of Honda's hapless failure to deliver a reliable and competitive engine. The team is widely expected now to intensify its efforts to find a solution with partners Honda or to seek a new temporary engine supplier.

Alonso , 35, and in the third and final year of his contract with McLaren, retired his car with an engine failure after a race spent fighting for mid-field positions. It was his third retirement in three races and may help to explain why he is so keen to take a break and miss the Monaco Grand Prix and take part in the Indianapolis 500 next month. "I have never raced with less power in my life," he said in one radio blast. When his team suggested a change of strategy, he said: "Do whatever you want, man."

Later, Alonso revealed: "The deficit in power and performance we had on the straights was amazing. Sometimes I looked in the mirrors at the beginning of the straights and saw the other cars 300, 400 metres behind... "So, I forgot completely about that car and started changing settings on the steering wheel and doing my own things, then the next thing I see when I come on the brakes is that car alongside me. "We were running close to the points but that's not enough. We never had the pace we had in Australia and China, and, in the end, we had a problem and we decided to retire the car. "When the red lights go off you're motivated and you start fighting, but you're so behind on the straights that there's no way you can defend your position. You fight in a fair way with everyone, but you don't enjoy the battle."

Vandoorne's social media post was accompanied by a comment in which he wrote: "Going for a run - you guys up to anything this Sunday?" McLaren's racing director Eric Boullier said: "What can I say? Fernando failed to finish and Stoffel failed to start. It was a bad day for McLaren-Honda and there is no point in pretending otherwise..." Alonso has suggested he is ready to consider offers from other teams later this year and reports in Spain have suggested he is already talking to Renault where he won his two world titles.

MERCEDES MULL TEAM ORDERS TO FOIL FERRARI: Mercedes team chief Toto Wolff says he is considering introducing team orders in a bid to halt Ferrari's momentum in this year's world championship.

In the wake of Sebastian Vettel's second win of the season in Bahrain on Sunday Wolff admitted that it may be difficult for Mercedes to continue to allow their drivers total freedom - and may ask new boy Valtteri Bottas to take the role of a 'number two' driver. The Finn was asked to allow three-time champion Lewis Hamilton to pass him in Manama as he laboured in pursuit of Vettel in a scenario that may be repeated regularly, if reluctantly.

"We don't like it at all," said Wolff, mindful of the team's tradition for open 'terms of engagement' that allowed intense competition between Hamilton and retired 2016 world champion Nico Rosberg in the last three years. "It's not what we have done in the last couple of years, but the situation is different now... So, it needs a proper analysis of what it means and where we are...

"We'd like to give equal opportunity at the start of the race. I think we owe it to them. "Then you see what we did in the this race -- we made the call, we made the call twice, because we felt it was the only possibility of winning the race..."

For the first time in four years, Mercedes have lost their supreme dominance and face a serious battle to hang on to their drivers' and constructors' titles as a revived Ferrari have gained the initiative. In Bahrain, Ferrari's aggressive strategy and tactics made the champions look rattled and ponderous as Vettel followed up his win in the season-opening Australian Grand Prix to take a clear lead in the championship.

By seeking not to give either driver any advantage over the other, Mercedes were unable to respond immediately and delayed their decision-making after Ferrari's early move to make an 'under-cut' pit stop. Wolff said he did not favour abandoning the team policy of giving the drivers' equality and rejected the idea of backing the driver who took pole position, or was most advanced on the grid. "That would be too harsh," he said.

"It would be the opposite of what we have done through the years. It's important, as we start the race, to give them equal opportunity. "We would probably have taken a different decision if Valtteri had run at the front, with the problem on the tyres, and Lewis would have been second, but with Vettel, between them, there was nothing we could have done. "That's why it was the perfect storm....

"It is our mind-set and our racing philosophy, until now, that we have given them both equal opportunity. Like here, if you have two cars starting on the front row - if they run second and first, you just have to let them race. "When you have a problem on the car, as we had (with Bottas' rear tyres), then it is a situation to consider -- to swap them - but with a Ferrari in between, we couldn't. Three races into the season, you don't want to go there yet."