Fernando Alonso will remain “first on the speed-dial list” for McLaren if required in the future despite his decision to quit Formula 1 at the end of the season, according to team boss Zak Brown.

Two-time F1 world champion Alonso will bring the curtain down on his 17-year stint in the sport this weekend in Abu Dhabi, making his final start before quitting in order to pursue other racing challenges from 2019.

Fernando Alonso F1 Driver Profile 2018

Alonso will remain part of the McLaren family after agreeing to race with the team in next year’s Indianapolis 500, and team boss Brown would be happy to call on the Spaniard if required to step in for any F1 duties.

“We certainly wouldn’t hesitate, if we needed a driver that’s not one of our current two, to have Fernando be the first on the speed-dial list,” Brown told Reuters.

“[Michael] Schumacher came back, [Alain] Prost came back. I wouldn’t rule that out.

“We’re very happy with our driver line-up for the future. That’s what we are very focused on at this moment, but never say never.

“He’s certainly driving at the top of his game.”

McLaren will field Carlos Sainz Jr. and Lando Norris in F1 next year, marking an all-new line-up as Alonso's current teammate, Stoffel Vandoorne, moves into Formula E.

Alonso is confirmed for four races so far next year, with three FIA World Endurance Championship rounds joining his Indy 500 run, but is set to add additional events to his schedule.

A return to the Rolex 24 at Daytona sports car race in January is in the works, albeit not with Brown’s United Autosports team, as it is not taking part in the event in 2019.

Instead, Alonso is thought to be chasing a seat with a DPi class team that would allow him to fight for overall victory, having finished 38th last year.