It doesn't take a footballing expert to tell that Cristiano Ronaldo is on the wane.Age appears to be catching up with the Real Madrid superstar who, at the age of 32, is no longer the fast and agile player he once was.Scoring certainly hasn't been a problem this season. In 22 La Liga games, Ronaldo has found the back of the net 19 times - the third highest in the league.Indeed, only Lionel Messi (25) and Luis Suarez (22) have scored more, with Celta Vigo's Iago Aspas (15) his closest challenger for third.But Ronaldo isn't used to being second best, nor third or fourth. Over the past decade, the Portuguese has been tussling with Messi for top spot - and to much success.He's been awarded the Ballon d'Or - and subsequently named the world's best player - on four occasions and won everything there is to win in European football.Times are changing, though. Ronaldo's performances are being scrutinised more than ever and it's simply because he's not as good as he was three years ago.The fact Zinedine Zidane felt comfortable with substituting him in the 72nd minute of Saturday's win over Atletico Bilbao spoke volumes about how he's no longer indispensable.In response to his number being shown on the board - bearing in mind Real were holding on to a slender 2-1 lead at the time - Ronaldo reportedly shouted, "Why me? F*** off".Ronaldo's decline is as clear as day but, if further evidence was needed, a rather embarrassing statistic involving John Stones has provided it.According to Squawka (see below), Stones - a centre-back for Manchester City - has completed as many take-ons this season as Ronaldo (17).

And just as an added comparison, prior to the weekend's set of fixtures, Messi had completed 71 successful dribbles, which is over quadruple Ronaldo's success rate.

Ouch. For so long Ronaldo has terrorised defences with his pace and skill but, as he enters the twilights years of his career, he's just not able to run at opponents with as much devastation.