Under the current Chelsea setup, there are no guarantees. Very few players can be certain of anything, especially game-time.
There's one man who's probably never enjoyed "untouchable" status before, but has now surely done enough to win himself a regular starting role in defense for Jose Mourinho's new-look Chelsea. The chap I'm talking about is Gary Cahill.
The official Chelsea website lists 27 first-team players, which tells you a lot about the competition for places at the club. Yet the Englishman has performed with such enviable consistency lately that the prevalent feeling is that he has a very strong case to be a first-choice selection for the West Londoners.
He's played some big matches in his brief Chelsea career, including a couple of European finals, and quite recently an away game against Manchester United. Cahill, to be fair to the man, has never looked out of his depth. He has improved leaps and bounds since his time at Bolton.
Jose Mourinho is known for building teams with a watertight defense. Cahill, meanwhile, is a typical English center-half, uninhibited when challenging in the air and uncompromising in the tackle. He's an archetype Mourinho defender.
He has immense recovery pace, while Gary's composure on the ball is often understated. He possesses all the attributes generally associated with a complete defender, while his readiness to put his body on the line is akin to that of club captain John Terry in his prime.
Terry, now 32, has regained the trust of the gaffer. He has started every one of the club's four Premier League games, and it appears that the other slot next to the skipper at centre-back is the one up for grabs. Cahill, with that view, must be in direct contention with David Luiz.
For purely academic purpose, if we were to study and compare the statistics and figures of Cahill against United and Luiz against Everton, there's only one winner.
David Luiz, in his first Premier League start of the new campaign against the Toffees, failed to win even one of the two aerial duels he contested. It must also be noted that the Brazilian made just one clearance through a game he played from start to end.
The combative, aerially dominant, no-nonsense centre-half that Chelsea could really use for difficult away trips is Gary Cahill. The 1-0 defeat at Goodison Park on Saturday could have been avoided had a defender less positionally naive than David Luiz been on the pitch.
Luiz is often credited for being more of a ball-playing centre-back. Then again, Gary Cahill is no amateur when it comes to passing. He has tried his hand at a similar role before, and passing diagrams from the games against Hull City and Aston Villa suggests he isn't too bad at it, provided Chelsea aren't stuck defending with their backs against the wall.
I'm not trying to suggest that he's at par with Luiz in this area; he certainly isn't. It is, however, my opinion that—with all aspects taken into consideration—his inclusion as starting CB for a big game is more imperative than Luiz's.
The interesting thing is that Luiz and Cahill, when viewed collectively, have the kind of characteristics that should enable them to play together. In theory, a Cahill-Luiz partnership should work. In practice, however, it seldom has.
With Branislav Ivanovic being viewed strictly as a right-back and Terry presently doing enough to justify his repeated selection, the only other competition for the spot discussed above comes in the form of Tomas Kalas. If it comes down to current form, Cahill is the most deserving man. If it comes down to big-match pedigree, it's probably still him. If the decision comes down to the primary instinct to defend, Cahill is yet again the most meritorious candidate.
And while he may be one of the game's most controversial characters, there's no doubting the fact that Jose Mourinho gives just rewards for merit.
*Statistics courtesy FourFourTwo's Stats Zone app.