Champions League - Final referee 'once headbutted by a fan'
But what sort of officiating can Chelsea fans expect from this 41-year-old who works as a financial director in his day job - and was headbutted by an unidentified fan only last year?
We take a look at the stats and stories in his career to date.
Proenca has taken charge of over 65 UEFA matches in the past, including the 2004 European U19 Championship final, and two Portuguese cup finals.
He has never refereed at a senior major championship but has been picked as Portugal's representative for this season's Euro 2012 tournament.
Across all competition this season Proenca has refereed 29 matches, brandished 169 yellow cards and 13 red ones (four of which were straight reds) and awarded eight penalties.
This shows that he is quicker to issue bookings than most Premier League refs: his average of over 5.8 yellows a game compares to only 3.1 in the Premier League.
In fact, the most yellow card-happy referee in England this season was Phil Dowd, but even he only averages 3.8 a game.
Proenca's average number of red cards is 0.45, which is again way above what we are used to in England where the average is 0.17.
However, experienced Champions League campaigners like Chelsea should be well aware that there tends to be more cards issued in European games.
In fact, Proenca's Champions League average this season is just 4.2 yellows in five games, while in the same number of matches Howard Webb averaged 5.4.
One of Proenca's matches was in the preliminary round, but the other four were all covered by Eurosport-Yahoo! reporters so we looked back at those matchcasts to see if the Portuguese whistle blower was ever the centre of attention - but he barely warrants a mention in most reports.
The one match where he seemed to have some difficulty was when Manchester City beat Villarreal 3-0 at El Madrigal, as he produced a performance that agitated the home fans so much they targeted him with a laser pen in the second half.
At one stage he was roundly whistled by the home fans for taking his time in allowing an injured Villarreal player return to the pitch and he also awarded Mario Balotelli what our reporter called a "somewhat contentious penalty".
"Balotelli nutmegged Jose Catala on the edge of the box and then fell to ground after feeling the elbow of Mateo Musacchio on his arm. It was a somewhat contentious decision, and Villarreal protested vehemently, but there was contact," read our report.
Proenca has issued two red cards in the Champions League this season – one for two bookable offences, the other a straight red, but neither decision was questioned by our reporters. Interestingly, both reds also came in stoppage time, limiting their impact on the game.
The match where Proenca effectively won his Champions League final place came in the Europa League when he took charge of the first leg of Schalke's Europa League quarter-final against Athletic Bilbao.
UEFA sent legendary Italian referee Pierluigi Collina to the match to assess Proenca and it is clear he must have come back with a positive report. The match itself was a thrilling end-to-end contest that Athletic won 4-2. There were six bookings in the match – three for each side.
An independent blog called 'Ref Marks' (http://refmarks.blogspot.co.uk) has assessed Proenca three times this season and has awarded him ratings of 79/100, 73/100 and 57.5/100.
Ref Marks' sole negative review came from a Champions League match between Internazionale and Marseille where their blogger commented that: "Proenca is always a bit hectic and chaotic, perhaps kind of organised chaos. The matches he has are basically under control, but there are always some problems with communication and keeping the players under control with natural authority."
Verbal communication should be easier in the Champions League final. Proenca can speak English and although he does not speak German, we checked with our office in Munich who said this "won't be a problem" as the vast majority of the Bayern team are fluent in English.
Chelsea fans looking for good omens might be pleased to learn that Proenca has refereed two Bayern Munich matches in the past and they lost them both. What's more, both clashes came at the Allianz Arena - a 2-0 reversal at the hands of Bordeaux in the 2009/10 group stage and 3-2 reversal to Internazionale last season that saw Bayern knocked out in the last 16 round on away goals despite winning 1-0 in Milan.
The Champions League final is far and away the biggest match of Proenca's career to date. He did referee the second leg of Manchester United's Champions League semi-final victory over Schalke last season, but with United having won the first leg 2-0 before going on to cruise to a 4-1 success at Old Trafford, it proved to be a low pressure affair.
Proenca was also the victim of a vicious attack from a fan last August while leaving a gym in a shopping centre near Benfica's stadium in Lisbon. He was headbutted by the fan and two of his teeth were broken as a result.
The attacker was never identified but Benfica released a statement about the incident saying: "Episodes like this strip sport in general and football in particular of its prestige and leave it poorer.
"Nothing can justify these types of acts and attitudes, because they reflect the worst of someone who has lost their values."
Benfica forgiveness only went so far, though, and they were again unhappy with Proenca in March when he took charge of Porto's 3-2 victory over their fierce rivals at the Estadio Da Luz. After the match Benfica's president Luis Filipe Vieira said that Proenca should "not be allowed to referee any more Benfica matches" after being unhappy with two decisions that led to Porto goals.
Chelsea's players would also do well to avoid gimmicky celebrations if they score. In a Europa League match in 2010, Proenca booked a Hapoel player for putting on a yarmulke after he scored a goal.
In a Champions League match between Real Madrid and AC Milan in 2010 Proenca fell to the ground after being pushed by Mesut Ozil, but it was deemed accidental by the referee.
So despite still being a young referee, the Portuguese ref has already had an interesting career. Let's hope it is the players, and not Proenca, who is making the headlines come Sunday morning.