London - Britain's Jenson Button will come out of retirement for "one race only" to replace Fernando Alonso in a McLaren at next month's Monaco Grand Prix, the Formula One team announced on Friday.
Alonso, like Button a former Formula One world champion, has been allowed to miss the race to compete instead for British-based McLaren at the Indianapolis 500, with both showpiece races taking place on May 28.
"Owing to Fernando Alonso's commitments with McLaren-Honda-Andretti over the weekend of the Indianapolis 500, which iconic race will take place on the same date (May 28th) as the Monaco Grand Prix, Jenson will take over Fernando's McLaren-Honda MCL32 for one race only: the equally iconic Monaco Grand Prix," said a team statement.
Button, who had regarded the concluding race of the 2016 campaign in Abu Dhabi as the last of his 17-season career, will be one of McLaren's two drivers at Monaco, with Belgium's Stoffel Vandoorne in their other car.
The 37-year-old Button remains under contract with McLaren, having agreed a two-year ambassadorial role with the team, but has yet to drive competitively this season.
Button, however, won the Monaco Grand Prix, the most glamorous race in Formula One in 2009 - the same year he took the world title with the now defunct Brawn team.
"I'm thrilled to be making a one-off return to Formula One racing, and I couldn't think of a better place to make that return than my adopted home Grand Prix of Monaco," Button said in the McLaren statement.
"I've won the race before, in 2009, and it's one of my all-time favourite racetracks.
"It's a tricky street circuit on which a good driver can really make a difference and, although the McLaren-Honda hasn't begun the season well, I think it may be more suited to Monaco than to the faster circuits that Fernando and Stoffel have raced it on so far this season.
"I realise we won't have a realistic chance of repeating my 2009 victory, but I think we'll have a opportunity to score world championship points, which will be very valuable to the team in terms of constructors' rankings."
Meanwhile Button, the last driver to win a race for McLaren in 2012, insisted it would not take him long to get used to the feeling of being in the cockpit of a Formula One car once again.
"I'm looking forward to pitting myself against the unique racing challenge that is the Monaco Grand Prix," he said.
"I'll drive the McLaren around Monaco in the simulator beforehand, and I reckon I'll be ready for the race after doing that.
"I'm supremely fit, having done a lot of triathlon training recently, so I have no worries on that score. And it'll be nice to say 'hi' to all my old Formula One mates, too, and hopefully to give the fans something to cheer about."
When McLaren announced on Wednesday that 2005 and 2006 world champion Alonso would miss Monaco to race in Indianapolis, the Spaniard said it was because he wanted to emulate Graham Hill by becoming only the second driver after the late Briton to win the 'Triple Crown' of the Monaco Grand Prix, Indy 500 and he Le Mans 24 hour sportscar race.
But the Indy 500 may have looked even more tempting given McLaren are currently last in the Formula One constructors' world championship after two races without a point.
McLaren, the second most successful team in Formula One history after Ferrari, in terms of race wins, have struggled lately, with Japanese engine-supplier Honda under fire for the team's poor results.
Alonso, 35, is now in the final year of a three-season contract with McLaren.
He joined in the hope of winning a third world title, but his best results with McLaren have been a trio of fifth-place finishes.
The Formula One season continues with Sunday's Bahrain Grand Prix.