The France international moved to Chelsea in a £30m deal from Leicester City in the 2016 summer transfer window after Kante helped the Foxes to win the Premier League title under Claudio Ranieri.
The defensive midfielder helped to transform Chelsea from a tenth-placed side to Premier League champions under Antonio Conte after a brilliant first season for Kante at Stamford Bridge.
The 26-year-old Chelsea star was named the PFA player of the year after the French star won the Premier League title in successive seasons with different clubs.
Kante injured his hamstring during October’s international break to rule out the holding midfielder for a 2-1 loss at Crystal Palace and a 3-3 draw with AS Roma.
Former Chelsea winger Nevin highlighted Kante’s absence as a big factor in the west London side’s recent struggles.
Nevin told Chelsea’s website: “I read a quote the other day which I intend to use very regularly from now on: ‘For every complex problem there is a solution that is simple, direct, understandable and wrong!’
“It just means people find it easy to grab at one thing when there is usually more complexity involved.
“I do almost always agree with this, even when talking about our current form, but I would still have to accept that maybe one point more than any other is the root cause. We are missing N’Golo Kante.
“It may be simple, direct and understandable but this time it is almost certainly right too.”
Chelsea will host Everton in the League Cup fourth round on Wednesday night as Conte looks to win the competition for the first time since taking over the reins of the west London side.
The Blues signed six players in the summer transfer window, including France international Tiemoue Bakayoko to partner Kante in Conte’s midfield.
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