Mozambique-born Fonseca has has built his managerial reputation after eyecatching spells at Shakhtar Donetsk and Roma and now it seems he has caught the attention of Tottenham Hotspur owner Daniel Levy.
After Tottenham's appointment of Mourinho failed to quench their desperate need for silverware, Spurs sacked the 'Special One', who subsequently returned to Italy, replacing Fonseca at Roma.
Failing to finish top four and losing the Carabao Cup final to Manchester City ended Ryan Mason's chances of landing the job full-time, while talks have seemingly broke down with Antonio Conte following his departure from Inter Milan.
With the summer transfer window now open, Tottenham's appointment of a manager is growing more and more urgent, and it now seems likely a bizarre (and costly) managerial swap deal might take place with Roma.
After a less than spectacular playing career, Fonseca immediately entered management in Portugal, where his success led to a job in Ukraine with Shakhtar Donetsk and then Roma in Italy.
Despite being only 48 years old, Fonseca has 14 years of managerial experience under his belt, during which he has won nine major honours.
With Fonseca inching closer to the Tottenham job, Planet Sport takes a look at the most crazy, unusual and iconic moments in his soccer career.
A modest start
Hailing from Mozambique, Fonseca played the majority of his soccer in Portugal. In his youth, he progressed through the ranks of Barreirense for five years before breaking into the senior squad in 1991.
Plying his trade as a central defender, Fonseca spent five seasons with the club in the third division, making 91 appearances and scoring six times.
Rather impressively, Fonseca transferred to Porto in 1995, but was deemed surplus to requirements and was loaned out before managing a senior appearance.
Fonseca then experienced a flurry of loan spells at Leca, Belenenses and Maritimo, before making a permanent switch to Estrela Amadora, where he saw out the remainder of his playing career.
In total, Fonseca made 249 senior appearances as a player, scoring 13 goals in the process.
For Spurs fans, Fonseca's playing career might not make great reading. But with the likes of Jurgen Klopp, Arsene Wenger and Jose Mourinho all failing to shine as a player, Fonseca is in good company.
Portuguese learning curve
After spending the twilight years of his career at Estrela Amadora, Fonseca called it quits on his playing career in 2005, when he was just 32 years old.
He wasted no time in entering coaching, and instantly took up a role as youth coach at the club, where he spent the next two years.
From 2007 to 2011, Fonseca departed on what seemed like a Portuguese road trip. The young manager undertook several coaching roles at different Portuguese clubs, most notably Pinhalnovense, who he led to the Taca de Portugal quarter-finals.
With more experience now under his belt, and still only 38 years old, Fonseca secured his first managerial job at a professional level at CD Aves. He led the club to a third-placed finish, narrowly missing out on promotion to the Primeira Liga.
But Fonseca continued to jump from club to club, never staying longer than a season, although he did have two separate spells at Pacos Ferreira either side of a stint at Porto.
Fonseca's spell at Porto was his first big shot in management, and it started well when he won Portugal's equivalent to the Charity Shield - Supertaca Candido de Oliveira.
However, after a torrid run of results, Fonseca found his Porto side trailing by nine points to domestic rivals, Benfica, and the young manager was relieved of his duties.
Following his dismissal, Fonseca returned to Pacos Ferreira for a season, before joining Braga in the 2015/16 campaign.
In Braga, Fonseca proved that his dismissal from Porto was merely a learing curve, not a setback, and he led the side to a fourth-placed finish in the league, while beating Porto in the Taca de Portugal final to claim his first major honour.
Success in Ukraine
After a rather fitting end to his coaching career in Portugal, Fonseca moved abroad for the first time when he became manager of Shakhtar Donetsk, replacing their legendary manager of 12 years, Mircea Lucescu.
With the pressure looming, Fonseca didn't disappoint. In each of his three seasons at the club, he managed to win both the Ukrainian League as well as the Ukrainian Cup.
In the 2017/18 season, Fonseca even managed to achieve a treble, acquiring the league title, cup and Ukranian Super Cup.
In his 139 games in charge of Shakhtar, Fonseca achieved an unbelievable win rate of 74.1%, losing only 17 of his games.
Fonseca's domestic dominance in Ukraine was enough to reward him with the league's Best Coach award in the 2016/17 season, but Fonseca also managed to impress in Shakhtar's European campaigns.
In the 2016/17 season, Shakhtar competed in the Europa League, and Fonseca managed to top the group with a perfect record which included back-to-back victories over his former club Braga.
In the knockout phase, despite an initial 1-0 away victory over Celta Vigo, Shakhtar were eliminated after falling to a 2-0 home defeat the week after.
However, after winning the Ukranian League in 2017, Shakhtar qualified for the Champions League where they were drawn against Napoli, Feyenoord and Manchester City.
Despite being pitted as underdogs, Fonseca led his Shakhtar side to second place in the group, winning all of his home games, and defeating Feyenoord away. Shakhtar were eliminated in the following round by Roma, but progressing from the group was a notable addition to Fonseca's CV.
Starring as Zorro
After winning the Ukrainian League in his first season in charge, Fonseca's Shakhtar side qualified for the Champions League in the 2017/18 season, where they were handed a tough group stage draw against Napoli, Feyenoord and Manchester City.
At the time, Napoli were flying high in Serie A and Pep Guardiola's Manchester City were at the peak of their powers, enjoying a 28-game unbeaten streak. Not many gave Shakhtar a chance of qualifying.
Shakhtar's Champions League campaign got off to a good start thanks to a 2-1 win over Napoli in the opening game, but expectations were sent crashing down to earth when goals from Kevin De Bruyne and Raheem Sterling inflicted a 2-0 defeat the following matchday.
Back-to-back victories over Feyenoord re-instilled hope in Shakhtar fans, but a 3-0 defeat in Naples left their European fate hanging in the balance.
Knowing they needed a result against a Manchester City side who had been unbeaten for months, Fonseca jokingly stated in the pre-match press conference that if his side qualified from the group stage, he would dress up as Zorro.
Courtesy of Ismaily and Bernard, Shakhtar took a surprising 2-0 lead before the half-time interval. Sergio Aguero pulled one back for the visitors in injury time, but it wasn't enough to stop the Ukrainian side from progressing.
As promised, in his following press conference, Fonseca showed his humorous character, entering the room dressed head-to-toe as Zorro. We've got to give it to him - he committed to the outfit.
Unfortunately for Shakhtar, their European dream ended a round later, against a club Fonseca would go on to join later in his career - Roma. After winning the first leg 2-1 at home, Roma saw out a 1-0 win in Italy to knock out Fonseca's side. But not before he provided us all with some high quality entertainment.
One too many substitutions
In an extraordinary turn of events, when in charge of Roma, Fonseca inadvertently made the mistake of making one too many substitutions during a Coppa Italia match.
Back in January 2021, Roma faced Spezia in a Coppa Italia round-of-16 clash. After falling to an early 2-0 deficit, Fonseca's side fought back to 2-2, leading the game into extra time.
Within just two minutes of the added 30, Fonseca's side were reduced to nine men after Mancini picked up a second yellow. This was quickly followed by the dismissal of goalkeeper Pau Lopez, who was sent off after trying desperately to make amends for a poor clearance.
Amid all the chaos, Fonseca was left with a mess to fix, although the way he went about it was rather… illegal.
Fonseca immediately ordered a double substitution, introducing both Ibanez and Fuzato to the fray. Whether Fonseca knew or not is unknown, but his double substitution took the tally up to six, with the Coppa Italia regulations only permitting five.
During extra time, Spezia scored two further goals to make them 4-2 winners, meaning Fonseca's mistake thankfully mattered little, but the moment still attracted a lot of media attention, leaving Roma no choice but to "discuss the matter internally".
Fonseca's mistake came just months after the club had committed an administrative error in their matchday squad against Hellas Verona in Serie A. Roma were again punished and the result was recorded as a 3-0 loss.