It was a largely uneventful clash in terms of entertainment value inside the Stadio Giuseppe Sinigaglia on Friday night, apart from Muani’s brace.
Muani broke the deadlock on 34 minutes against the run of play with a spectacular strike to bring the game to life.
Como levelled matters on the verge of the half-time whistle, only to gift Juve an 89th-minute penalty that Muani coolly converted to secure maximum Serie A points.
Juventus were under the cosh from the first whistle. Como constantly poured forward with Assane Diao, Nico Paz, Gabriel Strefezza and Alex Valle each coming close to beating shotstopper Michele Di Gregorio in the first quarter-of-an-hour.
Di Gregorio, who had to be on his toes, did have to pull off a great save to deny Lucas da Cunha’s long-range effort midway through the opening half.
It surprisingly took until the 26th minute before Juventus achieved their first attempt on goal.
Teenager striker Kenan Yildiz, given the nod to start over Dusan Vlahovic, picked out Federico Gatti in the middle of the box. Gatti’s header seemed to be heading into the bottom left corner only for ‘keeper Jean Butez to come to Como’s rescue.
Juve’s Nicolas Gonzalez sent his shot high and wide of the target on the half-hour mark. But then Mauni’s stunning finish visibly lifted the team’s confidence.
Muani, on loan from Paris Saint-Germain, rifled home with aplomb. The French international outwitted the close attention of two defenders, before unleashing a formidable shot that flew straight over the head of stunned Butez.
His fourth strike in his three Serie A games equalled Roberto Baggio’s 1990 record of scoring in each of his three opening league matches.
The Bianconeri started to find their feet after the goal without causing any real problems for Como.
For some reason Juventus took their eye off the ball on the stroke of half-time, and were duly punished. Missed chances from Como’s Paz and Ivan Smolcic was followed by Diao’s equaliser to stun the visitors.
Patrick Cutrone, whose tricky footwork caused Teun Koopmeiners to slip on the edge of the area, picked out the unmarked Diao who easily headed past Di Gregorio and into the top left corner from six yards.
The hosts, who had Juventus on the ropes for much of the opening half, deserved their equaliser during first half added time.
Como came out all guns blazing at the start of the second half, applying pressure on the Turin giants with Paz, Strefezza, Da Cunha and Valle all guilty of not extending the lead before 50 minutes were on the clock.
After Patrick Cutrone fluffed his close range chance by steering Strefezza’s cross wide of the target, Juventus head coach Thiago Motta made much-needed midfield changes. Khephren Thuram took over duties from Manuel Locatelli and Douglas Luiz replaced Koopmeiners on 61 minutes.
As Gonzalez’s shooting skills seemed to desert him. After he wasted two chances he was promptly hauled off by clearly frustrated Motta, with Francisco Conceicao given a 14-minute run out.
Como head coach Cesc Fabregas also made changes to his personnel, which worked wonders as the hosts blocked attempts from Luiz and newcomer Lloyd Kelly in the penalty area.
There was some last-gasp drama when overeager Butez accidentally injured Gatti when he tried to punch away the ball in the jam-packed penalty area. While Gatti received treatment, the referee awarded a spot-kick.
It was a tense two-minute wait before Muani stepped up to send Butez the wrong way and find the bottom left corner to make it a remarkable five goals from his first three Serie A games.
At this rate the 26-year-old should soon eclipse Juve’s top scorer Vlahovic. The Serbian striker, who has bagged eight league goals this season and 13 in all competitions, was left on the bench yet again but this time failed to make an appearance.
Juve’s triumph lifted them to fourth place in the league. Motta’s men sit one point ahead of Lazio, who host Monza on Sunday, and Fiorentina, who visit Inter Milan on Monday.