Changing a manager, whether at the start of a season or partway through the campaign, is an inherently risky move as clubs seek both an immediate impact and long-term improvement.

Thierry Henry’s atrocious start to life at AS Monaco currently stands as a stark example of how things can go wrong. For the following seven clubs, however, the gamble appears to be paying off handsomely at this stage in the European football calendar.

Lucien Favre, Borussia Dortmund

Replacing Peter Stoger, whose style of football failed to enthrall many Dortmund fans, Favre has brought a new verve to the Westfalenstadion. BVB are four points clear atop the Bundesliga and went 15 games unbeaten in all competitions to start the season, but that doesn’t tell the full story.

Thirty goals in 10 league games, plus the 4-0 demolition of Atletico Madrid in the Champions League last month, go further toward highlighting Favre’s impact. The former Nice coach has implemented a free-flowing attacking philosophy that perfectly fits his club’s strengths and allows stars like the effervescent Marco Reus and teenage sensation Jadon Sancho to shine. Favre’s summer signings such as Axel Witsel, Achraf Hakimi, and super-sub Paco Alcacer have only strengthened the side.

Thomas Tuchel, Paris Saint-Germain

It’s hard to improve on winning Ligue 1 by 13 points, but former Dortmund boss Tuchel, who replaced Arsenal-bound Unai Emery this summer, has done just that by turning a dominant giant into a multiple record-breaker.

PSG became the first team ever across Europe’s top five leagues to win 12 consecutive domestic games to start a season. They have scored 41 goals and shipped just seven along the way, and are already 11 points clear at the summit despite limited summer transfer activity. Plus, under Tuchel, Kylian Mbappe’s transformation into one of world football’s best players appears complete.

Maurizio Sarri, Chelsea

Sarri-ball is producing results at Stamford Bridge. Whereas Antonio Conte’s Chelsea last season were wildly inconsistent and deeply fallible, Sarri’s Blues are unbeaten through 17 games since August’s Community Shield defeat. The former Napoli mastermind has seamlessly integrated his fast-paced, possession-based style in west London, using teacher’s pet Jorginho as the base in midfield.

Only once have Chelsea really teetered on the brink of losing their unbeaten record, before Ross Barkley’s last-gasp equalizer saved them against Manchester United. Were it not for Pep Guardiola’s irrepressible Manchester City, Sarri’s side would surely be the title favorite.

Adi Hutter, Eintracht Frankfurt

Aside from Dortmund and Bayern Munich’s inauspicious start under Niko Kovac, the biggest story in German football right now is in Frankfurt. Adi Hutter’s arrival from Swiss side Young Boys to replace Kovac at Eintracht appears a masterstroke as last season’s DFB-Pokal champions have blossomed into an exciting, vibrant, and genuinely high-caliber side.

Most notably, Hutter is getting the most out of Frankfurt’s prodigious youthful attacking trio of Sebastien Haller, Luka Jovic, and Ante Rebic, who share 23 goals in all competitions this season. Eintracht may not hold a true title shout, with Dortmund looking unassailable and Bayern lurking, but a top-three finish, which would be their best placing in over a quarter of a century, is well within reach. And this is without mentioning the Europa League, in which they have four wins from four in a group containing Lazio and Marseille.

Rubi, Espanyol

Perpetually existing in the shadow of their illustrious rivals, Espanyol are going some way to addressing the unbalance in Barcelona this season. Rubi has lifted the club from mid-table obscurity to second in La Liga after 11 games, just three points off La Blaugrana’s pace. They have collected six wins to just two defeats, those being narrow, one-goal reverses away at high-flying Alaves and Real Madrid. Los Periquitos have won all five of their home games.

Perhaps their most remarkable feat, however, lies in their defensive record. Though Rubi’s men have scored a relatively modest 15 goals in 11 games, they have conceded just eight, a tremendously miserly mark behind only Atletico’s six and just over half as many as Barca’s 14. Whatever Rubi, who led Huesca to a first-ever promotion to La Liga last term, is doing in Catalonia, it’s working.

Vahid Halilhodzic, Nantes

The only manager on this list to have taken charge midseason, Halilhodzic has had the kind of immediate impact of which most new hires can only dream. When the former Japan boss took over in October, Nantes were 19th in Ligue 1; they are now 10th after a run of four consecutive victories in all competitions, across which Les Canaris have scored 14 times and conceded just once.

Halilhodzic’s effect is perhaps reflected most strongly in Emiliano Sala. The Argentinian striker had scored four goals in seven games prior to the Bosnian’s arrival; he has netted seven in five since the appointment. Nantes have a talented squad and, in their former prolific striker Halilhodzic, a beloved head coach. If the 66-year-old can keep the ship steady, Europa League qualification shouldn’t be out of sight.

Pablo Machin, Sevilla

Machin led Girona to 10th in La Liga last season – the best finish by a newly promoted side in 23 years – before joining Sevilla in the summer. The Spaniard’s philosophy promotes balance across the pitch and playing to key stars’ strengths, and that has unlocked his team’s potential this term. Sevilla currently sit third, just four points off the top, and are benefiting from a renaissance from the likes of midfield general Ever Banega and on-loan striker Andre Silva.

Silva’s transformation, in particular, has been remarkable while Pablo Sarabia’s 12 goals in 18 games are a testament to the freedom he’s being given going forward. Depending on Machin’s priorities, Sevilla’s league position may falter deeper into the season as the club chases a return to Europa League glory, but the 43-year-old currently has the Andalusians on track for their highest finish in a decade.