Adrian Clarke looks at key tactical points in Matchweek 3.
The Belgium internationals have been excellent across the Foxes' opening two fixtures.
In the absence of James Maddison, Praet, who made 12 Premier League starts last term, has been highly influential so far.
Castagne, who joined from Atalanta this summer, has also made an instant impact with two adventurous displays of his own.
With Maddison recovering from injury, Praet knew he needed to grasp his opportunity to shine.
He has done just that with back-to-back impressive displays.
Praet's willingness to push himself into the opposition penalty area is a far cry from last season when he often held back from doing so.
But in both matches thus far, he has had five touches in those advanced positions.
As a consequence of that tactical tweak, Praet now looks like an attacking midfielder who can get among the goals.
|BUR (H)||WBA (A)||2019/20 per 90|
|Touches in Opp box||5||5||1.51|
While it will be tougher for Praet to exert his influence going forward at the Etihad Stadium, he does have the technical quality to hurt Pep Guardiola's side.
It will be easier for Praet to receive the ball in space, if City use two attacking midfielders either side of one holding player.
Castagne's positive full-back play has breathed fresh life into the Foxes and help fill the void left by the injured Ricardo Pereira.
In his first two matches, the 24-year-old had six touches inside the opposition box and produced the same number of open-play crosses.
He scored with a header at The Hawthorns, teed up Harvey Barnes for a goal against Burnley, and his low cross forced an own goal to make it 2-1.
The last time he appeared against them was for Atalanta in a 5-1 UEFA Champions League defeat in 2019/20, with Sterling hitting a hat-trick.
Castagne will be keen to avoid a repeat as he and Praet aim to enhance their reputations even further.