Ronaldo limps out of training session with thigh problem

With the Champions League final just days away, Real Madrid will be sweating over the fitness of Cristiano Ronaldo, as the free-scoring Portuguese was forced to leave Tuesday's training session early, after appearing to aggravate his troublesome left thigh ailment.

Ronaldo, 31, collided with backup goalkeeper Kiko Casilla, and received treatment on the field before walking off, visibly perturbed.

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The club's marquee attacker has been hampered by a thigh strain in the latter stages of the season, most notably missing the first leg of the Champions League semi-final against Manchester City.

Though he was able to return for the second leg, and then play 45 minutes in the La Liga finale - scoring twice - his gingerly walk off the pitch during Tuesday's training session will undoubtedly raise concerns over his ability to feature in Saturday's final against city rival Atletico Madrid.

Prior to the session at Madrid's Valdebebas training ground, manager Zinedine Zidane claimed, rather ironically in hindsight, that he was not concerned about the fitness of his photogenic forward.

"There will be no problem with that," he said. "We had a game among ourselves on Saturday and [Ronaldo] didn't play, but [only] as a precaution as he felt something small. He is preparing for the final and I think we'll be in good shape physically - in the shape that we must be in."

Ronaldo has found the net 16 times in the Champions League this season - more than anyone else in the tournament - adding to his 35 La Liga tallies.