McLaren boss Zak Brown is leaning towards entering the British team into IndyCar next year.
Brown and McLaren's F1 racing director Eric Boullier visited the IndyCar paddock in Detroit between the Monaco Grand Prix and this weekend's race in Canada as the American continues to explore the opportunity to join the series. Michael Andretti, the owner of the Andretti Autosports team which helped McLaren and Fernando Alonso contest last year's Indy 500 and a likely partner in any full-time venture, was Brown's guest on Friday and Saturday in Montreal.
"We're seriously considering IndyCar," Brown said. We've been doing due diligence for quite some time. As stated before, if we're going to get into other forms of motorsport which McLaren has a great history in we need to do it in a way that first and foremost doesn't compromise our Formula One activities or we won't consider it.
"It needs to be commercially viable, something we feel we can be competitive in and fits our brand. It has to tick all of those boxes, not most of those boxes. We're not done yet with our due diligence but it's looking favorable so we will take a decision in order to be prepared for 2019 sometime in the upcoming months.
"If we're confident all four of those elements really tick those boxes then it's something that we will probably move forward on but we're not done with the journey yet."
The future of Alonso -- who is out of contract at the end of the year -- remains an intriguing part of the discussions and speculation about McLaren's next step. The Spaniard is competing in his 300th F1 race this weekend but has grown increasingly frustrated with the championship in recent years, having not won since 2013.
There is mounting speculation Alonso could stay on board with McLaren in IndyCar if it joined the series, something which would give him the option of returning to F1 once it has returned to competitiveness. Brown says discussions about the two-time world champion's future are ongoing.
"We're in talks with Fernando, as he said it was about this time last year that we started having conversations. He's been doing Formula One a long time, he's enjoying driving as much as he ever has. I think he's driving better than he ever has.
"As he's mentioned I think he's a little frustrated with Formula One being I think as he said becoming more of a constructors' championship than a drivers' championship. He loves Formula 1, he loves World Endurance and Daytona, so hopefully we will keep Fernando in the McLaren environment in some way, shape or form."