Lyon (AFP) – Real Madrid teammates Cristiano Ronaldo and Gareth Bale go head-to-head hoping to carry Portugal and Wales respectively to the Euro 2016 final on Wednesday. Here are five key factors in the often tricky relationship between the two most expensive players in football history:

– Bale’s first day –

After prolonged transfer talks with Tottenham Hotspur, Gareth Bale finally arrived in the Spanish capital on September 2, 2013 amid much speculation at how Cristiano Ronaldo would treat the pretender to his crown as king of the Santiago Bernabeu.

The initial encounter was a friendly one. A much more timid Bale than the one that will take to the field in Lyon appeared almost awestruck by Ronaldo’s presence as he was welcomed by the three-time Player of the Year at Madrid’s luxurious Valdebebas training ground.

– Bernabeu boo boys target Bale –

By his own admission Bale struggled with his form and fitness in his second season at Madrid. His case was not aided by Ronaldo’s demonstrative discontent on a number of occasions when Bale went for goal himself instead of picking out the Portuguese.

In the worst example, Ronaldo’s rage left Bale facing whistles from the Real crowd in a 3-0 win over Espanyol in January 2015.

– Bale scores, Ronaldo fumes –

Ronaldo is one of the most single-minded players ever and this could be clearly seen in a routine Real Madrid 2-0 win over Levante in March last year.

After Ronaldo’s initial acrobatic effort had been cleared, Bale expertly swept home the rebound to the delight of everyone with a Real affiliation other than Ronaldo. The Portugues stormed off disbelieving his wait to score with a bicycle kick continues.

It was not the first time Ronaldo was riled by a Bale goal. Amidst the euphoria when Bale netted Real’s decisive second goal in the 2014 Champions League final against Atletico Madrid to land the Spanish giants 10th European Cup, Ronaldo was one of the only players not to embrace Bale.

– World record Bale fee revealed –

In a bid to placate Ronaldo, Real had tried for nearly three years to insist the fee paid to bring Bale from Tottenham had not surpassed the £80 million paid for Ronaldo to Manchester United in 2009.

However, any doubts of Bale’s true cost were dispelled on January 21 this year when whistleblowing website Football Leaks published a copy of the contract Madrid signed with Spurs, detailing a total deal worth 100,759,417 euros (£85m).

– Bale wins respect –

Ronaldo unleashed a stinging attack of some of his lesser-known Madrid teammates after a 1-0 defeat to Atletico in February, claiming Real — then third in La Liga — would be top if everyone met his high standards.

Bale missed the match through injury and Ronaldo admitted he could not carry Madrid to victory on his own without Bale by his side.

“I don’t want to undervalue any of my teammates, but when the best aren’t there it is difficult to win,” said Ronaldo.

“I like to play with Pepe, Karim (Benzema), Bale, Marcelo. I don’t want to say that Jese (Rodriguez), Lucas (Vazquez), (Mateo) Kovavic are not good players, they are very good, but to win a competition you need the best.”