Royal–Thomian Rivalry refers to the competition, both in academics and sports between Royal College Colombo and S. Thomas' College, Mt Lavinia. Both schools have rich histories of academic excellence, as well as sport competition and school pride. Both were founded in the 19th century, and between them they have produced a large number of Sri Lanka's most prominent scientists, writers and politicians, as well as noted figures in many other fields.
Royal College, Colombo is a government-funded public school that accommodates approximately 8,000 students. S. Thomas' College, Mt Lavinia is an Anglican private school that has about 2,500 boys on roll and a branch network of three constituent colleges in Kollupitiya, Guruthalawa and Bandarawela with a total of over 5,500 students. Royal and S. Thomas' have been careful to preserve many parts of their proud history, retaining a number of traditions.
Royal–Thomian (the Battle of the Blues)
Known simply as the Royal-Thomian, the cricket match has been played by the schools since 1879. This annual cricket match is played for the D. S. Senanayake Memorial Shield, and is affectionately known as the Battle of the Blues due the colours of each school's flag. The first match was played between the Colombo Academy and St Thomas' College in 1879, thus was known as the Academy College match till 1881. The first match was played with schoolmasters participating as well as schoolboys. From 1880 onwards, only schoolboys were allowed to play in the match.
As of 2015, the tally stands as Royal having 34 wins and S.Thomas' with 34 wins. This is regarded as the most prestigious cricketing event in the country. The match itself is preceded by many activities including the legendary Cycle Parade which usually happens on the day before the big match, with the official objective of visiting the captain's house to encourage him.
Following the annual three-day match, known as the Big Match, the schools meet a week later for the limited overs match. Played since 1975, for the Mustangs Trophy, from which it gains its name.
In 2010, as part of Royal College's 175th anniversary celebrations the first ever Royal Thomian Twenty20 Cricket Encounter organized for the J. R. Jayewardene Trophy at the P. Saravanamuttu Stadium (The Oval).
The Royal Thomian rugby encounter held annually in the Michaelmas Term of S. Thomas and between the two sessions of Bradby Shield Encounter of Royal since 1955. Second only to the Bradby Shield Encounter (between Royal and Trinity) in prestigious rugby match in the country. It is played for the Michael Gunaratne Trophy.
Since 2002, The annual Royal Thomian basketball encounter is played for the prestigious D.S Senanayake Trophy. Every year an old boys match is also played. S. Thomas' won the first match for the D.S Senanayake trophy. As of 2013, the tally stands as Royal having 4 wins and S. Thomas' with 7 wins.
Since 2012 an U 15 match is also played. Royal College won the first U 15 match. As of 2013, the tally stands as Royal having 1 win and S. Thomas' with 1 win.
Played for the Dr R.L. Hayman Trophy since 1992, the waterpolo encounter is held in two sessions, one leg at the Royal College pool in Colombo and the second leg at the S. Thomas' College pool in Mt Lavinia.
The Senator Sir Cyril de Zoysa Shield of boxing is one of the most converted boxing tournaments in the island. The shield was presented in memory of Sir Cyril de Zoysa former President of the Senate of Ceylon.
Though tennis has been played at both schools for over fifty years, the first inter-school annual tennis encounter was organized between Royal and S. Thomas in 2003. It is played for the E F C Pereira Memorial Cup .
In 2009 both schools have agreed to begin an annual Royal-Thomian Swimming Championship, with the inaugural to being in May 2009. The even is due to be held at the swimming pools of each school on alternate years. Overall champions of the meet will be awarded the Creon Corea Memorial Challenge Trophy named after the late swimmer who represented Royal College in the early 1980s. A unique feature of this meet will be the relay events included for old boys of the two schools and the champions will be awarded the OTSC Challenge Trophy.
The Royal-Thomian Regatta is the annual regatta between the two schools. The Boat Race which is a coxed fours event initially began in 1962 and by 1966, it broadened out to give rise to the regatta having a card of six events, made up of 2 Single Sculls, 2 Coxless Pairs and 2 Coxed Fours which the 'Boat Race' is the most prestigious. The events take place at the Beira lake (alongside the Colombo Rowing Club) in Colombo around October each year with the T. N. Fernando Trophy awarded to the overall winner
- Hockey – Orville Abeynaike Trophy
- Rifle Shooting – Old Boys Shield
- There’s no Royal without S. Thomas’ and no STC without Royal!
- The Royal Thomian Derby
- Royal ends four-year drought – regains Mustang trophy
- Thomians retain Mustang’s trophy in tense finish
- Royal retain Hayman Trophy
- Royal-Thomian battle for Pereira Trophy
- Royal-Thomian tennis encounter
- Battle of the Blues spreads to the pool