The double Formula One world champion was on track at the Motegi Twin Ring Circuit at the weekend as Honda -- engine-supplier to the Spaniard's McLaren F1 team -- brought the curtain down on their motorsport year.
Alonso showed an impressive turn of speed as he raced down the pit straight ahead of his 23-year-old compatriot at the Honda Racing Thanks Day, attended by an estimated 20,000 fans.
Marquez became the youngest-ever MotoGP world champion in 2013 and clinched his third title at the Motegi circuit in October with three races to spare.
The Respol Honda rider paid tribute to Alonso on his official Twitter account after the event before asking his compatriot to return the favor.
"It was a pleasure to share track with @alo_oficial! Next time you teach me on four wheels," he tweeted.
What next for Alonso?
Alonso could be forgiven for thinking about switching from four wheels to two given how uncompetitive his McLaren Honda car has been over the past two seasons.
The 35-year-old finished 17th in the drivers' championship in 2015 and only sneaked into the top 10 this season.
It's a far cry from his championship winning years at Renault in 2005 and 2006 and his five years at Ferrari where he narrowly missed out on the drivers' title three times.
Alonso has a year to run on his current contract with the British team, but some of his fans would like him switch to Mercedes, following the shock retirement of reigning world champion Nico Rosberg.
Social media wags have already made light of this using the popular hashtag #PlacesAlonsoWouldRatherBe with @SomersF1 using a famous image of the F1 driver -- conspicuously sunbathing at the 2015 Brazilian Grand Prix after being eliminated early during qualifying -- placing it into a shot of the Mercedes UK headquarters in Brackley in southern England.
Alonso and Marquez were two of several Honda Racing stars appearing at the annual event.
Past and future McLaren teammates Jenson Button, who retired in November, and his 2017 replacement Stoffel Vandoorne were also on track as was Marquez's partner at Respol Honda, Dani Pedrosa.