Mystery Kovacic absence may continue unless Lampard tweaks his system

Frank Lampard made several tweaks to his team against Leicester in the desperate search for goals, and one would have imagined that one of those changes would be the introduction of Mateo Kovacic.
While famously goal shy himself, the midfielder gives the team a spark it otherwise lacks, and has the classy touch and dribbling skills to open teams up.
The fact he was left out again was really puzzling. Earlier in the season, Lampard took pains to individually praise the former Real Madrid player’s performances. How has now fallen so far down the pecking order?
Yes he’s been involved in a few bad results, but so has everyone who has played this season. Fans online and at the ground are mystified by his absence.
We write every week that we expect to see him back in the team soon, but maybe we shouldn’t be so sure. Clearly, unless they work on something new in this two week break, he doesn’t fit in with how Frank Lampard wants to play this season.