Carlos Alcaraz is a breath of fresh air in a tennis landscape dominated for decades by three men — and an absolutely gift for Spanish fans in particular.

But this joke — which we assume it was — might be going too far.

Alcaraz has returned from an injury that saw him miss this year’s Australian Open with a bang at the tour’s so-called fifth major in Indian Wells.

He stormed into a semi-final clash against Jannik Sinner — who is becoming a regular dance partner and potential long-term rival — with a 6-4 6-4 dispatching of Felix Auger-Aliassime.

But it was a sight up in the grandstand that proved the biggest talking point for tennis fans, when one man decked out in Barcelona gear unfurled a Spanish flag.

He’d made a glaring adjustment for Alcaraz’s match, taping over the word “Rafa” and adding “Carlitos”.

Even in jest, it was disturbing to see 22-time grand slam winner Nadal — who is currently out injured — so suddenly put out to pasture.

Nadal is still the reigning French Open champion, won two of the four majors last year and is certainly the last man you’d want to write off despite his body continuing to let him down at 36 years of age.

Fans erupted when an image of the supporter was shared on Reddit.

“What the f***, you know you could just get a new flag guy,” wrote one.

“Bahaha, this is hilarious. Poor guy is gonna have to get another flag when Nadal is back on tour,” added another.

“Typical glory hunter fan, no wonder he is wearing a Barca hoody,” wrote a third.

“High treason! This is hilarious,” added a fourth.

“Carlitos is a nice hopeful transition for Rafa fans when Rafa retires years from now,” a fifth wrote.

“Probably after 2024 and I can see Rafa going for 2025 if he still has hope for Roland Garros and why not.

“Federer fans did not have a countryman alternative that was young and upcoming like this overlapping so this is awesome.”

Alcaraz, the 2022 US Open winner, posted his first victory over Auger-Aliassime in four meetings to keep his bid to regain the world number one ranking on track.

“It’s wonderful to beat Felix finally, and the way I did it, playing at a great level,” said the 19-year-old, who called it perhaps his best match of the season.

Italy’s Sinner reached the final four with a 6-4, 4-6, 6-4 victory over defending champion Taylor Fritz and now has a chance to avenge his loss to Alcaraz in an electrifying quarter-final at the US Open last year.

That five-set battle lasted five hours and 15 minutes, its 2:50am finish the latest in US Open history. Alcaraz would go on to lift the trophy and become the youngest world number one in the history of the ATP rankings.

“We’ve played several times and all the matches have been very tough,” Alcaraz said. “I like this kind of challenge, I’m going to enjoy it.”

Alcaraz hadn’t dropped a set in reaching the quarters, but Auger-Aliassime was the first top-10 player he has faced this year.

This time, Alcaraz was ready for him, saying his prior defeats to the Canadian had taught him to “stay there.”

The two-hour clash was a thrilling display of athleticism and shot making from both players.

— with AFP