Red Bull Ampol Racing team manager Mark Dutton says intra-team squabbling cost his squad victory in Race 28 at the BP Ultimate Sydney SuperSprint.
Whincup and van Gisbergen found themselves line astern with 12 laps to go and four seconds adrift of race leader Brown who made his way to the front of the field on an undercut strategy.
Despite seemingly having more pace, van Gisbergen couldn't find a way past Whincup.
Such was the intensity of the battle that van Gisbergen got into the rear bumper of Whincup on several occasions.
The pair would make contact on several more occasions, with van Gisbergen being cast wide at least twice.
Despite calls from engineer Wes McDougall to let van Gisbergen by, Whincup held station in second.
Dutton, who rarely gets on the radio, even chimed in.
In the end, Whincup would finish second and van Gisbergen third while Brown hung on to his first Repco Supercars Championship race win.
“Our two drivers have been unbelievable the last three weeks working together and to hear what was going on in their garage, I was just laughing because it was just unbelievable to get a result like that.”
Asked for his view on whether the battle had cost his team a win, Dutton replied: “Certainly did, yeah.
“It's one of those things. From the garage, we saw it one way, from the cockpit it was seen another way.
“We'll debrief that and have a chat [about] which was the right way and which was the wrong way. It was probably pretty obvious, but we'll discuss it.
“You debrief. You talk through it. You say what you could've done better and what you didn't do better. We'll discuss it professionally and we'll move on.”
Team principal Roland Dane has not been trackside during the four-part Sydney swing; Dutton joked that he might have been axed mid-race, given the intensity of the battle and disobeying of team orders.
“I think I got fired during the race,” he laughed.
“Should be right. We'll see if that's confirmed.”
Van Gisbergen was left bemused by the series of incidents.
“It's a tough one,” said the 2020 Bathurst 1000 winner.
“It was obviously a good battle, probably entertaining, but I feel like we lost the chance at a race win.
“Anyway, congrats to Will and those guys. They've had some bad pit stops and some bad luck, but fast cars and it finally worked for them. So, congrats to them, well deserved.
Asked about the Turn 3 incident, van Gisbergen offered a short response: “It wasn't that good.
“At one point I was enjoying the battle but also I'm thinking, ‘We've got to win the race'. It is what it is. I had a fun battle, but I felt like we could've been up front.”
Van Gisbergen continues to hold a comfortable advantage atop the championship, 337 points clear of nearest rival Whincup.