There are rivalries among teams in sport. And then there are rivalries among those associated with sport. The lines between the two can get blurred at times, but certain caveats always remain.
In the context of the Indian Super League, only three head coaches can claim to have cultivated a competition among themselves - only Antonio Habas, Zico and Marco Materazzi are returning for their third ISL - and the one that has always produced fireworks is when Zico's FC Goa have come up against Materazzi's Chennaiyin.
Each of the five previous meetings between these two proud men - one a personification of the swagger associated with the Brazilian national team in the early 1980s, and the other a fiercely combative World Cup winner - had produced a win for the away team going into Thursday. There was also the small matter of the drama associated with those results, with Goa inflicting Chennaiyin's only home defeat in eight home matches in 2014, Chennai riding on Stiven Mendoza's first of two hat-tricks to romp to a 4-0 win last year, and then the final where Mendoza again was the catalyst for a last-minute heist.
Thursday provided a chance for both men to make a fresh start, with both yet to register a win in 2016. Zico stuck with the majority of the players he began with in the first two games, giving a start to Sahil Tavora in place of Mandar Rao Desai, while Materazzi opted to change almost half his side. Bringing in Karanjit Singh allowed him to play an additional foreign player up front, where Manuele Blasi came in, allowing Hans Mulder and Raphael Augusto to express themselves. Young left-back Jerry Lalrinzuala was given a start in place of Nallappan Mohanraj, an indicator of Materazzi's belief in youth, since Jerry had conceded the penalty to Atletico de Kolkata that prevented the defending champions from starting 2016 with a vital away win.
Karanjit was a bundle of nerves to start with, almost conceding a goal within the first 90 seconds, but then Chennaiyin were given space to work with thanks to Goa playing a lot narrower than usual. Chennai got that early goal, which came from Mulder after the Goans backed away from him. The visitors only looked threatening when they were able to get the ball through to Reinaldo or Rafael Coelho, but the midfield was unable to take control. This enabled Chennaiyin to double their lead, and from there it looked like there was no way back.
Zico's substitutions in the second half were odd as well, first pulling out Lucio and bringing on Richarlyson. That seemed like a tactic to go back to a favoured 3-5-2 to increase numbers in midfield, but Sanjay Balmuchu dropped back to help the defence. The other two changes were more positive, with Julio Cesar and Romeo Fernandes coming on, but both were given far too little time to make an impact. In fact, by then Chennai had created a few gilt-edged opportunities of their own and should have been out of sight but for their profligacy up front and some better defensive organisation from Goa.
A 2-0 win was the first by a home team in six matches now between Zico and Materazzi, and no less than what Chennaiyin deserved on the night. They showed urgency, quality and a calm head on their shoulders. These are attributes normally associated with Zico's Goa, but have not been shown often enough by Goa in ISL 2016.
To see Zico back in the ISL is a surprise. He had indicated last year during the semi-finals against the Delhi Dynamos team coached by his protégé Roberto Carlos that having completed his two-year contract at Goa, he had good offers from clubs in Europe and Asia. In comparison, Materazzi is just starting out as coach and had the added incentive of building on from a championship-winning season by coming back.
Zico of 2016 has looked jaded, frustrated and a bit low on inspiration. He has not been helped by injuries to Gregory Arnolin and Luciano Sabrosa, two of his most consistent defensive players from 2015. The team has looked short on quality and has now matched NorthEast United's three defeats on the trot to start a season in 2015, when they subsequently failed to make the playoffs.
If Goa and their proud head coach have to keep up their 100 per cent record of making the top four, that journey must start from the away match against 2014 champions Atletico de Kolkata on October 16.
Perhaps Zico can point to what his ISL rival Materazzi's men did last year, when they were required to win their last four league matches to avoid elimination - Thursday's goal scorer Mehrajuddin Wadoo said then that Materazzi asked his team to approach every game like a final - and they did even better, winning six of their last seven matches and pulling of a minor Margao miracle against Goa.