Zarco finished Sunday’s wet Thailand Grand Prix in fourth having piled pressure on Bagnaia in the latter stages for the final podium place.
The Pramac rider was careful in how he approached the battle, given Bagnaia is Ducati’s leading championship hope and is now just two points behind Fabio Quartararo after the Yamaha rider struggled to 17th in Thailand.
Having seen no clean way of overtaking Bagnaia, Zarco backed off to finish fourth.
But Zarco revealed that since the San Marino GP, Ducati has instructed all of its riders to not fight Bagnaia too hard for positions that were not victories or podiums.
“It's clear. [I can be] Incisive on Marc, less incisive on Pecco,” Zarco told Canal+.
“The track really dried out on the last five laps, the last four laps, and it was too late to think about winning. But still... The sooner I manage to pass Pecco, maybe I can try something and get away from [Miguel] Oliveira.
“But as there was really only one line and when we got away the bike slipped, well it was still complicated. Two laps passed, and two laps before the end we saw that the victory was not there.
“So, it was good to play it smart. These are conditions in which I am aiming for victory, because I am comfortable in these conditions.
“I was hoping that it would dry out a bit earlier, because at the beginning with a lot of water it was very complicated, you can't see the rider in front, and so even if you brake late... maybe you can get through, but you don't want to make a disaster either.
“And that's what was tricky in combat. It was a good weekend and a good race, because fourth place in conditions like this is long, it's hard, but it's nice to finish with points, a good place and almost a podium... let's say [I] left to Pecco.
“Since Misano we have some race instructions, difficult to apply when we are not fighting with Pecco, and until now it was not the case.
“But today it was the case, and for a victory Ducati doesn't block anything; for places other than podium, yes we give the advantage to Pecco. But here, in these conditions, it was the victory we had to aim for. Fourth is very good.”
Senior Ducati management was seen going straight to the Pramac garage after the race, with Zarco saying the marque’s general manager Gigi Dall'Igna thought his decision not to force the issue on third place with Bagnaia was “gentlemanly”.
“The championship is missing, I've already missed too many races [to score points], and how can I say... Gigi was very emotional.
“To have left the podium he thought it was very gentlemanly of me. But we saw that I was at ease behind, but as soon as we left this [racing] line it became risky and it would have been a shame to make a big mistake.
“So that's it. I was clearly well received by Ducati, they said a big thank you.”
