Liam Rosenior might have downplayed the significance of Chelsea's win against Antonio Conte's Napoli in the Champions League after a comeback victory that secured a place in the last 16. But outmanoeuvring a manager who once occupied his office at Stamford Bridge and guided them to the Premier League title should rank high among the new Blues manager's career achievements.

Managing in the Champions League for only the second time after taking charge of the club earlier this month, Rosenior was the novice facing a master tactician whose legacy looms large over the club. With Chelsea 2-1 down in the hostile Naples atmosphere, they were facing the prospect of having to go through the two-legged play-offs to keep themselves alive in the competition.

But the 41-year-old English manager's proactive tactical switches in the second half sparked a stunning Chelsea comeback with Joao Pedro scoring twice to secure a top-eight finish.

"It's not about me," Rosenior said after Chelsea became only the second team to defeat Napoli on home soil in 21 matches. "My job is to win games here as the manager of Chelsea, so it's not about where does it rate in my career. I'm not really fussed."

While Rosenior and Chelsea celebrated securing a direct spot in the last 16 with victory at the Stadio Diego Armando Maradona, Conte was left staring into a familiar abyss at full-time. His Napoli side finished 30th in the 36-team league phase as for a fourth time a team under his management failed to progress to the Champions League knockout stages.

The result in Naples could prove to be of great importance for Rosenior whose appointment in place of Enzo Maresca was hardly greeted with open arms. Rosenior's lack of elite experience - having moved from sister club Strasbourg after stints with Derby County and Hull City in the Championship - saw him labelled by some as a 'yes man'. He also experienced the wrath of the fans who voiced anti-ownership chants questioning the ambition of the BlueCo.

Rosenior has been adamant from the start that his reply must be through results. And he has put together an impressive set of results in his first weeks with five wins in six matches and the latest over a former Chelsea favourite should win him the confidence of more supporters.

"These players lost a manager that they really respected for reasons that are beyond my control or knowledge," Rosenior told TNT Sports. "So when you go through that as a young group, to accept a new manager the way they have done and for them to work as hard as they have done is a credit to them."

"It's not about me or my ego or trying to prove anything. I'm trying to do the very best I can with my group, with my staff and hopefully we can have more and more really good nights like this."

Rosenior's introduction of Cole Palmer at half-time provided assists for both of Joao Pedro's goals while Trevoh Chalobah added defensive solidity after coming on later in the half as the Blues restricted Napoli to a single shot on target after the break.

The Chelsea manager added: "I'm learning all the time about my team, about what we're capable of. I really wanted to be front-footed today. I wanted to go out and win the game." His impetus was rewarded with a win that helps Chelsea avoid adding a two-legged play-off to their already busy schedule.

"It's massive - that is huge for us to be able to work with the players on the training round," Rosenior said. Bigger challenges await Rosenior and his young squad as they enter the business end of the competition but the London-born coach is optimistic.

"You have to enjoy this job," he said. "We're the luckiest people in the world to do this job. You have to enjoy these moments, but we want more. You're in the Champions League, so at the end of the day you have to play against the best and beat the best."

Conte lifted the Champions League as a player in 1995-96 but has experienced nothing but despair as a manager in Europe's premier club competition. Wednesday was the 50th game the Italian has managed in the Champions League across spells at Napoli, Tottenham, Inter Milan, Chelsea and Juventus. Conte has 17 wins, 17 defeats and 16 draws in those matches.

He has collected 61 points from 44 matches he has overseen in the group stage/league phase at an average of 1.39 points per game - a rate lower than his contemporaries Carlo Ancelotti, Massimiliano Allegri, Jose Mourinho and Pep Guardiola. Meanwhile, he has managed 618 games across all other competitions, winning 374 and suffering only 110 defeats, collecting 2.03 points per game at a win rate of 60.5%.

But in the Champions League, the win rate plummets to just 34%. His sides have been knocked out in the group stage four times, with only Jorge Jesus (five) experiencing more group-stage exits as manager since 2012-13, and the round of 16 twice. A quarter-final exit with Juventus in his maiden adventure in the competition remains the best run he has managed, though he guided Inter to the Europa League final in 2019-20.

Potentially adding to his frustrations, both Juve and Inter reached Champions League finals within two seasons of him departing. He has also failed to win the Coppa Italia despite a decade of dominating Serie A as a coach and an FA Cup with the Blues in 2018 remains his only cup triumph.

"It's disappointing," Conte said of the defeat. "Chelsea were better in the final third, but the players had a good game. I wanted to stay in this competition. We're proud nonetheless as we played well and deserved more." But after another Champions League setback, the pattern is difficult to ignore - Conte might be the master of league campaigns but he continues to come up short in knockout football.

Watch highlights of every Champions League game from 22:00 on Wednesday on BBC iPlayer and the BBC Sport website and app. There will also be a Champions League Match of the Day on BBC One on Wednesday, from 22:40 to 00:00.