The Challenge Cup is a knockout rugby league cup competition held annually since 1896, with the exception of 1915–1919 and 1939–1940. It involves amateur, semi-professional and professional clubs.
The ongoing implications of the Coronavirus pandemic have forced changes to the structure of the 2021 Challenge Cup because amateur clubs were not able to enter the tournament for the early rounds.
Instead, the 13 English clubs from the Championship - including Bradford, Featherstone and Widnes - were joined by West Wales and two other clubs from League One.
The 12 Super League clubs join the competition this weekend, at the third-round stage, which will be followed by quarter-finals in May, the semi-finals on 5 June, and the final at Wembley on Saturday, 17 July.
The current holders of the Challenge Cup are Leeds Rhinos, who edged Salford Red Devils 17-16 thanks to a late Luke Gale drop-goal to win the competition for the fourteenth time.
Wigan Warriors are the most successful club in the history of the competition, winning the cup a record 19 times.
The BBC will once again bring you live action from the 2021 Challenge Cup, broadcasting two third-round fixtures, two quarter-finals, the semi-final and final.
You can catch-up on the first and second-round ties here.
This weekend is the third round and the BBC will be showing St Helens v Leeds Rhinos and Catalans Dragons against Wakefield Trinity.
Saturday, 10 April
14:00-16:30 BST- St Helens v Leeds Rhinos - BBC One, BBC iPlayer and the BBC Sport website & app
16:30-19:00 BST - Catalans Dragons v Wakefield Trinity - BBC Two BBC iPlayer and the BBC Sport website & app
There will also be a Rugby League World Cup 2021 forum on the BBC Red Button from 19:00-19:30.
Coverage of the two games and forum will be available uninterrupted on this page and on BBC iPlayer.
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