Juventus will be sweating after Cristiano Ronaldo suffered an injury during Portugal’s European Championship qualifier against Serbia.The 34-year-old pulled up with what appeared to be a hamstring injury and left the match in the 29th minute.Ronaldo is due in action for Juventus when they take on Ajax in the first leg of their Champions League quarter-final on April 10.The second leg will be played the following week on April 16.So Juventus, who have a near-unassailable lead in Serie A, will be hoping it’s nothing too serious.

Those European matches could well have been on Ronaldo’s mind when he gestured that he needed to be replaced.

If it was just a precautionary move then the Italian giants won’t be too concerned. But if it’s more severe, then they will be worried.

Ronaldo goes off injured v Serbia

The five-time Ballon d’Or winner was making just his second appearance for his country since last summer’s World Cup in Russia.

Portugal’s qualifying campaign for the 2020 European Championship got underway with a 0-0 draw at home to Ukraine.

Fernando Santos’ side fell behind early against Serbia, Real Madrid’s tormentor Dusan Tadic scoring a penalty in the seventh minute.

But a stunning long-range effort from Danilo Pereira levelled the scores before half-time.

Click HERE to see Pereira’s strike.

The contest finished 1-1, leaving Portugal third in Group B.

Ukraine top the group, having followed up their draw against Portugal with a win against Luxembourg on Monday evening.

Portugal and Serbia will meet once again in Serbia when the qualifiers continue in September.

Ronaldo will be fully aware that these are his final opportunities with the national side and he'll be desperate to appear at Euro 2020 and attempt to defend the trophy with his international teammates.