You know a rivalry is big when it has its own nickname and the Panathinaikos – Olympiacos rivalry has that. It is known as the Derby of the eternal enemies and also as the Mother of all battles.

There are a number of different elements to the Olympiacos- Panathinaikos rivalry. The first is cultural. Panathinaikos represents the upper classes while Olympiacos is more for the working classes. While this may not be the case to the extent it was hundreds of years ago, the club's have maintained these flavors till today.

The next element of the rivalry is on field success. Panathinaikos has won the league 20 times, the Greek Cup 16 times and finished runners-up in the European Cup once when it lost to Ajax in the final.

Olympiacos has won the league an astonishing 37 times and the Greek Cup 24 times. Now you can tell why these two are referred to as the Kings of Greek football.

The Olympiacos- Panathinaikos rivalry is also fuelled by the strength of Panathinaikos in Europe. Given Olympiacos domestic success you would this would carry on into Europe but the reverse is true. Panathinaikos' performance in reaching the 1971 European Cup final is still the only time a Greek side has made the final and they did it the hard way. The defeated the Czech Slovan Bratislava in the second round before taking out Everton in the quarter finals on away goals. In the semi finals they faced the Yugoslav Red Star Belgrade. Red Star won the first leg 4-1 at home but Panathinaikos bounced back in the second leg winning 3-0 and advancing to the final on away goals. That Panathinaikos side were managed by the great Ferenc Puskas who used all his experience to lead them to the final. They were no match though for an Ajax side led by the incomparable Johan Cruyff.

Panathinaikos made it to the semi finals of the 1985 European Cup. They eliminated Dutch Champions, Feyenoord in the first round and were drawn to meet Northern Ireland's Linfield in the second round. It was a tough tussle and Panathinaikos only made it through 5-4 after the second leg was a 3-3 tie. A good draw saw Panathinaikos drawn with Gothenburg in the last eight and there the Greeks got by 3-2. Liverpool were just too strong and won the tie in a convincing 5-0.

Olympiacos made it as far as the quarter finals in the 1999 Champions League but Juventus knocked them out 3-2 on aggregate.

Olympiacos hasn't seemed to master the art of winning on the road and in European football this is vital if you want to have any success. In 52 Champions League matches Olympiacos has played on the road, they have only won three. That is a staggering level of underachievement for a side which is so strong. By contrast they have won 27 of their 52 matches at home and only lost 10.

Another factor in the Panathinaikos – Olympiacos rivalry is the support bases of the two teams. Olympiacos has more support outside of Athens and all over the rest of Greece while the fans of Panathinaikos are centered in Athens. There isn't much support for them outside of the capital.

Because these two teams are so dominant in Greece, the Olympiacos- Panathinaikos rivalry plays out in the transfer market. For the most part, both sides are made up of Greek players but then there is a smattering of Brazilians and players from other nationalities. Stars such as Rivaldo, Christian Karembeu and Giovanni have played for Olympiacos. Over the years, Panathinaikos has fielded the likes of Gilberto Silva, Julio Cesar da Silva, Robert Jarni, Paulo Sousa and Juan Ramon Veron.

Their respective home grounds are another part of the Panathinaikos – Olympiacos rivalry. Olympiacos play at the Karaiskakis Stadium. It was used for the 1896 Summer Olympics but has been renovated since. It has a capacity of 33,334. The stadium has a four star UEFA rating which means it is eligible to host the UEFA Cup final which it hosted in 1971. The final was between Chelsea and Real Madrid with Chelsea winning a replay. Panathinaikos play at the Olympic Stadium which was used for the 2004 Summer games. This ground hosted the 2007 Champions League final between Milan and Liverpool which Milan won. It also hosted the 1994 Champions League final; also won by Milan. The 1983 European Cup Final between Hamburg and Juventus was there as was the 1987 Cup Winners Cup final between Ajax and Lokomotive Leipzig.

Panathinaikos' reputation as being the club for the elite is going to be reinforced when they move into their new stadium called the Votanikos Arena. It will have a capacity of 46,000 and will have a 5 star UEFA Rating. It is scheduled to be complete by the start of the 2010-11 season. It is going to have all the modern amenities and will give a real advantage.

As the Panathinaikos – Olympiacos rivalry keeps going, the two are going to find themselves in a separate league to the rest of the Greek club sides. Like the situation in Scotland, they are going to need each other for competition otherwise there will be no one to challenge them and no one to keep things interesting.