Squad rotation has become a very sensitive subject as far as Rafael Benitez is concerned during his tenure at Stamford Bridge.
Of all the subjects that appear to get under his skin, questioning his tendency to change the starting XI on a game-to-game basis upsets him the most.
Just ask the former Chelsea captain and assistant manager Ray Wilkins, whose opinion on the cause of Ashley Cole’s hamstring injury led the Spaniard to brand his comments worthy of an April fool.
As much as the club’s fans would argue to the contrary, the fault does not completely lie with Benitez for everything that has gone awry at Stamford Bridge.
Look beyond the small collection of players that tend to hog the headlines, like Juan Mata and Eden Hazard, and the squad has been shown to lack in quality.
With Chelsea having a fixture schedule that would test the best in Europe, the fringe players are coming more and more under scrutiny.
If Chelsea are to successfully achieve their three targets of finishing in the top four, as well as winning the FA Cup and Europa League, then it will depend on their spare parts as much as the main engine room to deliver.
Significantly against Rubin Kazan last night, the number of fringe players Benitez picked was significantly fewer than he chose for the woeful Premier League defeat against Southampton just five days before.
Ryan Bertrand, Yossi Benayoun and Victor Moses all had a point to prove though against a Russian side boasting an unbeaten record in the competition away from home.
The focus was particularly on Bertrand due to Cole being ruled out for at least another couple of weeks, during which the club have key League games against Sunderland and Fulham and the FA Cup semi-final with Manchester City.
Bertrand’s fortunes have dipped since the dizzy heights of earning a Champions League winner’s medal on debut in last season’s final, with even some of the club’s fans questioning his future at the club. However, the 23-year-old ensured his more celebrated team-mate was barely missed both defensively and offensively.
Moses, who joined from Wigan for £9m last summer, has also found life at Chelsea a bit more difficult of late having initially enjoyed an impressive opening to his career in west London.
His departure for the African Cup of Nations upset his rhythm, yet the Nigerian international was looking much more like his old dynamic self, running at his opponents with purpose. There was a finely struck goal to show for his efforts too.
Only Benyaoun, as has been the case since he joined from Liverpool in 2010, failed his audition and was largely anonymous throughout, apart from one fancy flick in the build-up to Chelsea’s third.
Naturally, Benitez will continue to lean heavily on Cole, Mata, Hazard and Co, but at least in Bertrand and Moses he has players that he can turn to during the challenges ahead.