Spain - By contrast, Cristiano Ronaldo's contribution to Real Madrid can't be questioned, at least until recent weeks.
The Portuguese has become the club's all-time leading scorer in just his seventh season and won the Ballon d'Or in each of the past two seasons.
Yet, by his own remarkable standards, Ronaldo's form has dipped this season.
A return of 13 goals in 15 games would be sensational for most players, but there has been a worrying trend of those strikes coming in batches against weaker opposition rather than when it matters most.
Indeed, Ronaldo has failed to net in nine separate games this season, including when Madrid have dropped points against Atletico Madrid and Sevilla and in two Champions League clashes against Paris Saint-Germain.
His behaviour at the end of the second meeting with the French champions drew particular ire in the Spanish press as he warmly greeted PSG coach Laurent Blanc and president Nasser Al-Khelaifi, fuelling rumours that he could be ready to move on from Madrid at the end of the season.
Transfer speculation has also surrounded Bale with Manchester United believed to be keen to bring the 2012/13 Premier League Player of the Year back to England.
Gareth Bale also isn't helped by comparison to Neymar, who Barcelona bought for a similar outlay in the same summer he joined Madrid.
In the time that Lionel Messi has been on the sidelines, Neymar has arguably been the best player in the world, taking the lead role to propel the Catalans to the top of the table.
Bale has never been able to put the consistency shown by the Brazilian together at Madrid.
When he did finally return to the side from injury last time out at Sevilla, he and Ronaldo looked like strangers as Madrid succumbed to their first defeat of the season.
Another one on Saturday in the 'El Clasico' and it could be the beginning of the end for one, if not both.