McLaren boss Ron Dennis: No apology for F1 line-up decision delay

While Dennis admitted that the deal for Alonso to return was done "many, many weeks ago - much earlier than anyone even imagined", he said Button had only signed his new contract on Wednesday night prior to Thursday morning's announcement that the 2009 F1 champion would stay on, with Magnussen relegated to a reserve role.

Dennis said the initial concern had been to avoid disrupting the end of the 2014 campaign, and then the possibility of third cars for next season had raised the prospect of an Alonso/Button/Magnussen race line-up.

"If you actually look at the hurdles, I make no apologies for the level of consideration that I gave to the decision," he said.

"We were faced with a remote possibility that we could overtake Ferrari in the constructors' and I didn't want to destabilise the last two races.

"We had a very important aero test that took place on the Saturday of Abu Dhabi, and I didn't want to destabilise that test by having one driver motivated and one driver demotivated.

"Then on the Tuesday following the Abu Dhabi Grand Prix there was a Formula 1 Commission meeting and on the agenda were two or three things that had relevance to the decision-making process.

"As is widely known now there are some teams, including McLaren, that have an obligation to run three cars if the world championship grid falls below 16 cars. So I was balancing the possibility of that happening."

He also felt it was philosophically right to have an in-depth debate within the McLaren management.

"This decision did not even need to go to the board - this decision could have been one that I took having consulted with Eric [Boullier] and Jonathan [Neale].

"And I could have just said 'these are the drivers'. But how silly would that have been?

"We function with a whole series of values, one of which is to be collaborative."

Dennis added that he understood fans' impatience at the long wait for an announcement.

"I know that the media, fans and other people - sponsors, etc - put on every bit of pressure they could for a decision," he said.

"But that decision sits with me and I take the consequences of the results in 2015. No one is going to cut me any slack at all if the decision is wrong.

"So I can feel completely justified in taking my time, because while it was a little bit painful for the two drivers, the pain they had then is nothing in comparison to the pain that I will suffer if the decision proves to be wrong."