Daniel Ricciardo says the prospect of losing long-standing race engineer Simon Rennie at Red Bull was a key factor in deciding the Aussie to move from the Milton Keynes-based outfit to Renault.
Ricciardo spent the first half of the 2018 season mulling his future, weighing extending his stay at Red Bull or moving on to a new challenge.
The seven-time Grand Prix winner took many criteria into account before ultimately setting his choice on Renault.
But Rennie's decision to travel less with the race team and accept a factory role at Milton Keynes was an important element to consider for Ricciardo who had worked alongside the race engineer since 2014.
"There were a lot of reasons, but losing Simon - I knew he wasn't going to engineer this year, if I stayed at Red Bull, and I thought I had a good relationship with him, and there were some unknowns," said Ricciardo, speaking in Hungary before the summer break.
"I was certainly comfortable with him. If I knew he stayed, I don't know if that would've been the deciding factor, but it was another [thing] - obviously when you've got the Honda concern and a few others, I guess that was another little thing.
"As I said, there were lots of these little things which probably added up - I don't want to say ‘concerns’ but unknowns, ‘concerns’ is probably a bit disrespectful."
In addition to Renault, Ricciardo also held talks with McLaren for 2019. He remembers the 2018 Hungarian Grand Prix weekend as the moment where everything started to come to a head.
"Sunday night we had to start to really decide what to do, and I was like 'I'm just going to go out tonight, have a few drinks, and maybe I'll find my answer with a few friends'," he remembers.
"And then on the Monday it all kind of started to kick off a bit more."
Ricciardo flew to Los Angeles the following day, and the long flight brought him his pick.
"When I landed, I was like 'alright, yellow and black'."