Both of Newcastle's centre backs clearly perform better alongside Jamaal Lascelles, who is now key to the club's success.
Jamaal Lascelles might be Newcastle United's captain - and a star performer so far this season - but his place in the side was in doubt at the start of the campaign.
The former Nottingham Forest man benefited from Lejeune's withdrawal in that game and did not lose his place again until his own injury blow against Bournemouth.
With Lascelles at the centre of defence - alongside either Lejeune or Clark - Newcastle looked solid at the bank.
There remained doubts over his long-term place right up until the moment he came out of the side, however, with many assuming Lejeune and Clark to be the club's best pairing.
But that has not proven to be the case, with Newcastle's form tailing off drastically since Lascelles' injury.
Lejeune and Clark have both looked suspect, too, and now Magpies fans are counting down the days for Lascelles' return.
The potential England prospect has developed into a fine defender, but few realised quite how crucial his leadership role was to the success of the team.
With every passing poor defensive performance, Lascelles becomes more crucial.