Martin Whitmarsh has strongly denied team orders were employed during Sunday's Spanish Grand Prix.
With Sergio Perez rapidly gaining on team-mate Jenson Button over the closing stages of the race, the duo were poised to rekindle their on-track clash from Bahrain three weeks earlier.
On that occasion Perez ran into the back of Button and later banged wheels, much to the Briton's immediate post-race anger that sparked clear-the-air talks between the duo, Whitmarsh and sporting director Sam Michael.
But any hope of another wheel-to-wheel duel at Barcelona's Circuit de Catalunya was dashed when a radio message was issued to Perez to conserve his tyres at a time when he was half a second behind Button.
The immediate interpretation was McLaren had issued a coded call to Perez not to attack Button, but Whitmarsh defended the directive.
Whitmarsh, who refused to intervene in Bahrain given McLaren's long-held belief in allowing its drivers to race, said: "Did I fear a repeat of Bahrain? No.
"Did we ask him to back off and not fight? No, we didn't. In truth, there was a battle on in prospect, but at the end Checo's tyres were completely shot.
"We could see by the tyre wear he was likely to run out of rubber by the end of the race, and he very nearly did. If you look at his tyres there is nothing there.
"He flat-spotted at one point because his tyre temperatures went off on the last set in chasing Jenson, and he is entitled to chase.
"It was tight, but obviously not quite as close a contest as we had in Bahrain. Even Checo said at the end his tyres were finished.
"So the message was not tactical, it was practical."
"The message was not tactical, it was practical" - Martin Whitmarsh on the radio message issued to Sergio Perez to conserve his tyres at a time when he was closing fast on team-mate Jenson Button
Via his Twitter feed yesterday, Perez also reinforced the comments from Whitmarsh as he wrote: "Just want to tell everyone, the radio message was all about to save the tyres.
"Never a team order. Can't wait for Monaco."