Napoli earned an important win in a big test on Thursday, bettering Club Brugge 1-0 in Belgium to win their fifth Europa League match in the group stage and guarantee themselves the top spot in Group D. Doing it on the road with a backup-heavy side made the feat all the more impressive, and a first Napoli goal for Vlad Chiriches made the win all the sweeter.

Napoli started the match with a curious formation, with Jose Callejon working as their center forward -- a position he hasn't played in several years -- and with Marek Hamsik and Omar El Kaddouri operating as wide forwards, a natural fit for neither player. That makeshift front lone, brought on by Maurizio Sarri resting Gonzalo Higuain and Lorenzo Insigne, plus the injuries to Dries Mertens and Manolo Gabbiadini, would cause Napoli problems throughout the match, as no one seemed terribly comfortable in their roles, and all three players made numerous mistakes that are uncharacteristic of themselves.

We also saw the first career start for on-loan midfielder Nathaniel Chalobah, a key test for the young Chelsea man. He's barely played this season for Napoli, but did quite well today, showing plenty of energy going back and forth in midfield and looking surprisingly calm and assured in possession. He also performed well in defense, breaking up several counters and proving very disruptive to Club Brugge's attack. There's certainly still some rough edges to work on with Chalobah, but he's definitely earned himself more playing time after that performance.

The standouts, though, were on Napoli's backline, especially Vlad Chiriches and Kalidou Koulibaly. With Brugge breaking hard on the counter every time they won the ball back, Napoli's defenders had to be on their toes all match long, but by and large they were incredibly impressive, leaving the Belgian team stonewalled at every effort and holding them to one single shot on target all match long.

That one shot on goal actually came when both Chiriches and Koulibaly had a shaky moment -- an attempted clearance from Koulibaly was poorly directed and deflected off Club Brugge attacker Felipe Gedoz and back into the box. Chiriches tried to shield Jelle Vossen off the ball to let Gabriel pick it up, but the ball's momentum died a bit quicker than he judged and Vossen was able to poke through his legs to get a shot off. Fortunately, his effort was weak and went straight into Gabriel's arms, but that could have been a very embarrassing moment for Napoli.

After that, though, Chiriches and Koulibaly were a stone wall, breaking up everything that came their way. Koulibaly was a beast in the air, cutting out numerous tries at high balls or long passes over the top from Brugge, and Chiriches used his athleticism and ever-improving tactical sense to cut out run after run after run attempted by Brugge players to stop attacks before they had a chance to become dangerous.

Chiriches' most valuable contribution to the match, though, came on the other end of the pitch. Late in the first half, Chiriches was up for a corner kick when Callejon missed his try at a header. The Romanian defender sniffed out the opportunity and ran over to strike it on a half-volley, hammering it home past a totally oblivious Sebastien Bruzzese to score his first goal in a Napoli shirt.

After that, the match was mostly a containment effort of sorts for Napoli. They dominated possession the rest of the way, passing circles around a Club Brugge team that fatigued much quicker than their Italian opponents. That fitness edge in the Napoli squad being honed by Maurizio Sarri has been coming up huge in recent matches, and by the end of the game they were essentially just playing keep-away with their foes. Sarri's substitutions made the side increasingly defensive -- which makes sense, since his only attacking player on the bench was 17 year old Antonio Negro -- and there was no real incentive for Napoli to push for another goal. They had the tally they needed, and the result they wanted secured.

The 1-0 win in Belgium gave Napoli their fifth group stage win in five matches, and clinched the top spot in the group for the partenopei. That was guaranteed anyways by FC Midtjylland losing to Legia Warsaw -- the Danes would have had to win both of their remaining matches, with Napoli losing and coming out short in a huge goal differential swing to lose the top spot -- but making sure to guarantee it with a win away from home is a sweet added bonus.

Now Napoli can turn their attention to Inter Milan this weekend with a largely rested and motivated squad. The top spot in their Europa League group is secure -- now it's time to go first in Serie A.

Napoli: Gabriel; Maggio, Chiriches, Koulibaly, Strinic; Lopez, Valdifiori, Chalobah (Allan 81'); Hamsik (Hysaj 69'), Callejon (Ghoulam 77'), El Kaddouri

Goal: Chiriches (41')

Club Brugge: Bruzzese; Meunier, Mechele, Denswil, de Fauw; Vormer, Simons (Pereira 88'), Vazquez (Diaby (81'); Gedoz (Vanaken 81'), Vossen, Izquierdo

Goals: None