The Dutchman suffered a damaging defeat to Real Madrid in El Clasico at the weekend, with star man Lionel Messi cutting a frustrated figure once more as the club sank to 12th in the table.
Pirlo has also faced early questions about his formations with his current champions sat outside the Champions League places in Serie A, and will also have to contend with Cristiano Ronaldo missing the fixture due to coronavirus.
Here, Sportsmail delves into the key issues facing both bosses ahead of the showdown.
Ronald Koeman (left) and Andrea Pirlo (right) are under pressure ahead of their clash tonight
Paulo Dybala will form the heart of Juventus’ attack as they look to defeat the Catalan side
When things go wrong it appears only natural to blame others, and that’s exactly what Koeman did when launching a tirade against VAR to award Real Madrid a crucial penalty at Camp Nou.
But the former Netherlands boss’ outburst at the implementation of VAR has failed to mask the issues that hampered Barcelona in El Clasico.
The first involves the conundrum of Lionel Messi, who looked extremely lively in the first half of El Clasico and barring some superb Madrid defending from the likes of Casemiro may have notched his first goal in the fixture in more than 900 days.
Koeman blamed VAR after his side’s El Clasico loss but his complaints did not mask the issues
However, his impact was minimal in the second half and after Sergio Ramos had scored the penalty, it had almost extinguished.
Koeman placed Messi directly behind central forward Ansu Fati and in the first half it reaped some reward, with the former finding Jordi Alba who laid the ball on a plate for the 17-year-old Spain international to cancel out Federico Valverde’s opener.
But too often did Messi appear to be the sole flagbearer for Barcelona in attack, and the supporting cast simply could not provide the necessary support in terms of decoy runs which the likes of Luis Suarez, Neymar, David Villa and even Thierry Henry used to provide the Argentine in abundance.
That cast instead involved two 17-year-olds in Fati and Pedri, as well as Philippe Coutinho, who this season has shone more centrally with two goals and as many assists rather than being shunted out to the left as he was on Saturday.
Lionel Messi cut a frustrated figure again and appeared to be the sole flagbearer in attack
Philippe Coutinho also struggled out on the left having flourished centrally this season
The young players such as Pedri and Trincao are likely to come good in the future, but whether their relative inertia now as well as Coutinho’s struggles out wide will force Koeman into a tactical re-think in Italy remains to be seen.
A possible change in Turin could see the re-introduction of the forlorn Antoine Griezmann into the starting XI, who appeared to be more naturally suited to the role played by Coutinho at the weekend.
But as El Mundo wrote following the match, Griezmann was left wondering when his next opportunity to perform his famous confetti blowing celebration will be.
The £108million Frenchman has yet to record a goal or assist for Barcelona this season and has been vocal about his frustration at playing on the right wing since Ronald Koeman took over.
Coutinho’s struggles could see Antoine Griezmann (right) reintroduced to help Messi in attack
‘The coach knows where to put me,’ Griezmann said about national team manager Didier Deschamps when on international duty earlier this month. ‘I take advantage of this situation, of this place, of the confidence of the coach and my team-mates.’
Griezmann’s compatriot Ousmane Dembele – who cost the club £96m from Borussia Dortmund – is another player that Koeman is struggling to integrate into the first team plans.
Dembele scored after coming off the bench against Ferencvaros in their first group game, but was again wasteful when brought on El Clasico despite using his pace to get into threatening positions.
Concerns have also been raised about the favoured double pivot of Sergio Busquets and Frenkie de Jong, with worries the former, now 32, no longer having the legs to run back and press the pacy attackers of the modern game nor bring the ball forward with any great purpose.
Doubts have also emerged about the double pivot of Sergio Busquets and Frenkie de Jong
KOEMAN’S RECORD AS BARCELONA BOSS
Win ratio: 50 per cent
The duo were easily bypassed by Madrid and dominated the midfield, with one report in Spain slamming the Netherlands midfielder as ‘insignificant’ in the midfield, and Koeman may feel he needs to turn to former Juventus midfielder Miralem Pjanic to strengthen the engine room despite his fondness of de Jong as the second man in midfield.
The Bosnian has only started one game since arriving at Camp Nou in the summer, and appears very much to be Koeman’s back-up to the Busquets-de Jong pivot, but would likely add more stability to midfield if Busquets is given a breather.
Josep Bartomeu’s resignation as president of the club on Tuesday as well as the rest of the board of directors may have been the start of the long-term clarification Barcelona desperately need to resolve off-the-field issues in terms of finances and player recruitment.
But in the short-term on the field, Koeman has certainly been left with more questions than answers, and no immediate solutions in terms of players’ form and potential replacements for those underperforming appear forthcoming ahead of the clash with Juventus.
Miralem Pjanic could add some more energy to the Barcelona midfield against his former side
Andrea Pirlo’s tactics and use of formations have been questioned during his fledgling managerial career at Juventus, but his more immediate concerns have been out of his control.
Despite beating Dynamo Kiev in his Champions League debut, the former midfield maestro is worried about the showdown against Barcelona due to the club’s long injury list.
The hosts will be without Cristiano Ronaldo, who once again tested positive for Covid-19 on Tuesday and will therefore not only miss the chance to challenge himself against old foe Messi once again but also hands the Pirlo the near impossible task of replacing his unique goal threat.
Paulo Dybala and Alvaro Morata do however provide excellent cover in Ronaldo’s absence, with the duo having already scored three goals against Barcelona in recent years.
Andrea Pirlo has a number of injury issues to contend for the clash against Barcelona
Morata scored against Barcelona in the 2015 Champions League final while Dybala scored twice and was a menace for the Catalan side in the 2017 quarter-final.
The Argentine playmaker has had his issues with Dybala this season, having struggled with physical issues initially before he reportedly raged at director Fabio Paratici in the tunnel at his non-existent role since Pirlo took charge after being left out against Crotone.
But he will now look to steer his side to exploit a Barcelona defence that conceded plenty of chances to Madrid aside from the three goals Zinedine Zidane’s men did score.
Dejan Kulusevski and Federico Chiesa are probably the best wide players in Serie A right now, and the Swede demonstrated his goal threat by firing in the equaliser that spared Pirlo his first defeat as Juve boss against Hellas Verona.
Former Fiorentina winger Chiesa can also take players on but also possesses incredible strength and endurance which makes him an even bigger threat going forward.
Pirlo faces the near impossible task of replacing Cristiano Ronaldo who is out with coronavirus
Pirlo’s problems however appear more intense at the other end of the field, with stalwart Giorgio Chiellini out and fellow experienced centre-back Leonardo Bonucci struggling with muscle fatigue, while Matthijs de Ligt is an expected absentee after having shoulder surgery last month.
That leaves Turk Merih Demiral as the only fit and recognised centre-back. The Turkish defender is considered one of the best up and coming defenders in Europe and has received the backing of Pirlo having played the full 90 minutes in their last two Serie A games.
But the 22-year-old remains relatively inexperienced but will nevertheless be forced to lead the defensive line alongside Brazilian Danilo, with the former Manchester City player more suited to play at full back.
Pirlo has tried out different formations during his opening fixtures with the manager alternating from a 3-5-2 to a 3-4-1-2 and then to a 3-4-3 set-up.
Juventus do have excellent cover up front in the form of Paulo Dybala (left) and Alvaro Morata
A return to a three-man defence with two attacking full-backs in Danilo and Juan Cuadrado seemed to have worked, but with his injury woes in defence as well as the need to find greater balance, he will now be forced to choose an unfamiliar four-man defence against Barcelona.
The system may well favour Kulusevski and Chiesa, who will be allowed to cause havoc out wide, but could cause some defensive issues due to the unfamiliarity of the system.
Pirlo was critical of his midfield after the draw against Verona, stating that his side are yet to find their creative focal point.
That issue has been exacerbated by the fact he has failed to settle on a midfield two so far, with the manager struggling to find the right balance of attack and defence from the options available to him.
Juventus’ issues come in defence with Giorgio Chiellini out and Leonardo Bonucci doubtful
Weston McKennie, Aaron Ramsey, Rodrigo Bentancur and Adrien Rabiot are all options, while Arthur has played in four of Juventus’ matches this season.
However, the Brazilian in particular has yet to convince his coach that he can become the midfield dynamo Pirlo requires and will require a strong performance against his former side.
Arthur showed all the limits of a player accustomed to the Spanish game, and the former Barcelona star will have to quickly get used to the aggressive and tactical side of Serie A football.
Doubts also surround the manager himself, who is still yet to fully convince he can lead the club to much-coveted European glory given his early league struggles.
Their injuries along with Matthijs de Ligt means Merih Demiral is the only fit centre-back
Demiral is likely to be partnered in central defence by Danilo, who is naturally a full back
The former Italy World Cup winner has certainly brought a change of style to Maurizio Sarri, but with experimentation still ongoing in his squad and questions still to be answered, a few concerns linger as to whether a man with such little managerial experience can be the man to find the solutions.
‘We will count on the players we have available. Barcelona are strong and have great champions, we must play a great game,’ Pirlo said ahead of the game.
‘The players will certainly have to sacrifice themselves and play a great match.’
Pirlo’s tactical decisions appear to have drawn mixed results, with the current champions fifth in the current top-flight standings, but he will need this latest switch to come off if he is to pull off the first major victory of his managerial career.
Arthur faces a fight on his hands to convince Pirlo that he can become Juventus’ midfield cog