Only 2 clubs in world football could realistically sign Cristiano Ronaldo if he leaves Juventus this summer

• Cristiano Ronaldo appears to be on his way out of Juventus this summer.
• Calciomercato reports PSG and Manchester United are the only realistic destinations for him.
• Ronaldo scored 118 goals for Manchester United between 2003 and 2009.

Cristiano Ronaldo could realistically only join Paris Saint Germain or Manchester United if he leaves Juventus this summer, according to Italian soccer publication Calciomercato.

Ronaldo, 36, appeared to say goodbye to Juventus after he was left on the bench for the club's final game of the season at the weekend.

In a cryptic Instagram message posted on Monday, he wrote: "Nothing compares to the feeling of knowing that I've left my mark in the countries where I've played."

He concluded the post by saying: "Thanks to everyone who took part in this journey!"

The Portuguese forward has been linked with a return to his boyhood club Sporting Lisbon in recent months, however Calciomercato says he will wait until the twilight his career to make that move.

Instead, the Italian publication, which is a subsidiary of Gazzetta Dello Sport, says only PSG or United, another of Ronaldo's former clubs, are possible destinations for him this summer.

Calciomercato says PSG will attempt to bring Ronaldo to Paris in the event that star striker Kylian Mbappe leaves for pastures new.

The French club, which is owned by billionaire Qatari businessman Nasser Al-Khelaifi, is also one of only handful in world soccer that could afford to pay Ronaldo's $38 million annual salary.

Manchester United, on the other hand, is unlikely to be able to afford such wages, but Calciomercato says the Europa League finalist is ready to open its doors to Ronaldo again, albeit on its own terms.

Ronaldo joined United as a teenager after leaving Sporting in 2003, signed by United's legendary manager at the time, Sir Alex Ferguson.

During six seasons at Old Trafford, he would go on to establish himself as one of the best players in world soccer, scoring 118 goals and winning three Premier League titles before moving to Real Madrid in 2009 for a then-record transfer fee of £80 million (around $113 million at current prices, $131 million then.)