Strikers Eden Hazard and Gonzola Higuain scored two goals each, plus Defender David Luiz solitary effort ensured that Chelsea whitewashed Huddersfield Town and bounced back to winning ways at Stamford Bridge.
Blues boss Sarri had been under fire after Chelsea suffered their heaviest Premier League defeat for 23 years in a humiliating 4-0 loss at Bournemouth on Wednesday.
Amid reports the Italian is already in danger of the sack less than a year after taking charge, he was indebted to his old friend Higuain for lifting the gloom around Stamford Bridge.
Higuain, signed on loan from Juventus at Sarri’s behest after their successful spell together at Napoli, opened his account early in the first half of Chelsea’s biggest win of the season.
It was the start of an influential display from the Argentine and, with Eden Hazard free to return to his preferred role on the flanks after a spell up front, Chelsea looked far more vibrant.
Hazard’s controversial penalty doubled Chelsea’s lead before halftime after referee Paul Tierney ruled Cesar Azpilicueta was fouled inside the area, when the offence actually took place just outside.
That welcome piece of good fortune for Sarri was followed by further goals for Hazard, Higuain and David Luiz after the interval as Chelsea ended a run of two successive league defeats in emphatic fashion.
After winning for only the second time in their last five league matches, Chelsea climb back into fourth place above Arsenal, who trail by three points and face Manchester City on Sunday, as they battle to qualify for the Champions League.
While Chelsea’s winter of discontent won’t seem so bleak for Sarri now, the Blues remain at a crossroads.
Much sterner tests await than Huddersfield, who are rooted to the bottom of the table and look destined for relegation after an 11th defeat in their last 12 league games.
Chelsea face a season-defining period that includes the League Cup final against Manchester City and meetings with Manchester United in the FA Cup and City and Tottenham in the league.
Sarri hasn’t helped his cause with rigid tactics and dubious man-management – conducting a long inquest with his players after the Bournemouth mauling and claiming they don’t understand even the basics of his system.
The 60-year-old is adamant his philosophy will work if he is given time.
But for ‘Sarri-ball’ to succeed, he needs Higuain to hit the ground running.F
The Argentine had been off the pace in his first two Chelsea appearances, but he brings a more physical and authoritative presence than the unlamented Alvaro Morata.
Chelsea had failed to score in three of their last four league games, but Higuain ended that barren streak in the 16th minute.
When N’Golo Kante slipped a neat reverse pass towards Higuain, the 31-year-old timed his run perfectly to beat the offside trap, held off his marker and smashed a fierce first-time finish into the roof of the net.
Higuain isn’t all brute force. His clever movement was too much for Huddersfield to handle, and he was just off-target after gliding onto Marcos Alonso’s cross.
Chelsea’s constant pressure was rewarded with that dubious penalty on the stroke of halftime.
With Huddersfield offering so little threat, Azpilicueta was free to roam forward and the Chelsea defender’s run was ended by a crude shove from Elias Kachunga.
Hazard ignored Huddersfield’s protests as he calmly sent Jonas Lossl the wrong way from the spot.
That was Hazard’s 16th goal of the season and the 17th arrived in the 66th minute.
Ross Barkley’s fine pass put Hazard through on goal and he produced a deft first touch to round Lossl before finishing with a flourish from a tight angle.
Chelsea had their swagger back now and Higuain unfurled a majestic 20-yard strike that whistled into the top corner in the 66th minute.
Luiz’s 86th minute header deflected in off Kachunga to seal the rout.