Carnegie Challenge Cup fifth round - Crusaders v Catalans Dragons
Venue: Racecourse Ground Date: Sunday, 9 May Kick-off: 1530 BST
Coverage: Exclusively live on BBC TWO & online, score updates on BBC Sport website and BBC Radio 5 Live
Crusaders and Catalans Dragons clashed in a non-English Challenge Cup tie on Sunday, with the Crusaders narrowly losing 34-35.
To mark the big game, I compiled my best post-war XIII of Welsh players who have crossed the rugby divide from union to league.
Name: David Watkins
Union: Newport League: Salford, Swinton
Dai Watkins travelled north to Salford from Newport for £15,000 in 1967 and his 221 goals for Salford in the 1972/73 season is a record.
Watkins, who went on to coach Great Britain, also holds the record for the longest-scoring run as he played and scored in 92 consecutive matches for Salford from August 1972 to April 1974.
He toured with the Great British Lions in Australasia in 1974 and is the only player to have captained both the Great British Lions league and union teams.
Name: Billy Boston
Union: Army, Cardiff Internationals Athletic Club League: Wigan, Blackpool Borough
Boston was was selected for the GB Lions tour of Australasia in 1954 after playing only five matches for Wigan after switching codes.
He scored a then record 36 tries on tour and equalled the individual Test match record by scoring four tries versus New Zealand in first test in Auckland.
The 31-times capped GB star was the first non-white player to be selected to tour and his 478 tries for Wigan is a record.
He played six times at Wembley in the Challenge Cup final and is arguably the greatest Welsh rugby league player.
Name: Lewis Jones
Union: Llanelli League: Leeds, Wentworthville (Australia)
Jones played seven times for Wales rugby union before the age of 20 when he turned professional for a then world record fee of £6,000.
He scored a record 278 points on the 1954 GB Lions tour of Australia/New Zealand in 1954 and set a world record 496 points in a season in 1956/57 for Leeds and representative teams.
Gus Risman captained Salford to beat Barrow to the Challenge Cup in 1938
Name: Gus Risman (captain)
Union: Cardiff Scottish League: Salford, Workington
Risman switched codes as a 17-year-old and played rugby league for a staggering 25 years scoring 4,052 points in 873 matches.
He was a member of three Lions touring parties in 1932 and 1936 before skippering the 1946 squad.
He joined the newly formed Workington Town club as player-coach in 1946 and led them to Championship and Challenge Cup wins within six years.
Risman became the oldest competitor to play in a Challenge Cup Final at the age of 41 years when he led Workington to a 18-10 victory over Featherstone Rovers in 1952.
Name: Clive Sullivan
Union: Army, Cardiff League: Hull FC, Hull Kingston Rovers, Oldham, Doncaster
The Great British Lions skipper of 1972 was the first black captain of any national British sporting side when he led GB to World Cup success in 1972 in France - scoring a spectacular 80 metre try against Australia in the final.
Sullivan scored a hat-trick on his debut as an unnamed triallist for Hull against Bramley in December 1961 - going on to score 406 tries in a career spanning 23 years.
He crossed the Hull divide and scored a century of tries for both Hull and Hull KR and won Challenge Cup finals with both.
Name: Jonathan Davies
Union: Llanelli League: Widnes, Warrington
Jonathan Davies won GB's match against Australia in 1994
One of an elite few union international captains to switch codes as the former Wales union skipper scored 112 points in 13 Great Britain league caps.
The prolific points-scorer grabbed 342 points in the 1990/91 season and was Warrington's leading try and goal scorer in his first season after leaving Widnes in 1993 as Davies was named Man of Steel.
Davies scored a memorable try against Australia at Wembley Stadium in October 1994 to inspire an 8-4 GB win.
Name: Billy Banks
Union: Maesteg League: Leeds, Wakefield, Huddersfield, Whitehaven, Salford
Banks gained 17 Welsh caps at scrum-half - captaining his country on one occasion - and starred for Great Britain against France three times. Banks appeared in Huddersfield's last Challenge Cup Final win at Wembley against St Helens in 1953, scoring a vital try direct from the scrum.
Name: Jim Mills
Union: Cardiff League: Halifax, Salford, Bradford Northern, North Sydney, Widnes, Workington Town
The fiery forward, who suffered 20 dismissals both in Britain and Australia, was a member of two Great Britain Lions tours to Australasia in 1974 and 1979 and the holds six GB Test caps.
On returning to England in 1972 after three years in Australia, Mills matured into one of Britain's finest front-rowers and played 14 major finals including three Challenge Cup appearances for Widnes at Wembley.
Name: Tommy Harris
Union: Newbridge League: Hull FC
Harris is one of rugby league's all-time outstanding hookers as he was not just a ball-winner in the scrums, but a crafty midfield distributor.
The Welshman played more than 444 games, including 25 Great Britain Tests and two Lions Tours, between 1949 and 1967. Even though, he suffered concussion and was on the losing side of the 1960 Challenge Cup final, Harris became the only hooker to win the man-of-the-match trophy.
Kel Coslett was man-of-the-match as St Helens won 1972's Cup
Name: Kelvin Coslett
Union: Aberavon League: St Helens, Rochdale Hornets
Coslett was a fine leader at full-back, loose forward or finally at prop. He was a prolific points-scorer for St Helens as in 531 appearances, he amassed 3,413 points. Captain Kel led the Saints to numerous Challenge Cup and Championship final successes in the 1970s, winning the man-of-the-match trophy in their 16-13 final win over Leeds in 1972.
Name: Trevor Foster
Position: Second row
Union: Newport League: Bradford Northern
Foster was a speedy second-row forward who gained 16 Wales and three Great Britain caps. His excellent running and handling skills ensured he scored 140 tries in 462 games, the most by any Welsh forward, and scored six tries in one match for Bradford. He served his club for more than 60 years as he was club timekeeper after retiring from playing.
Name: Colin Dixon
Position: Second row
Union: Cardiff League: Halifax, Salford, Hull KR
Dixon was signed at 17 by Halifax such was his pace and footballing ability, but the centre quickly emerged as a devastating runner from the second row.
He won many trophies and captained Halifax before being signed by Salford for a then world record fee of £15,000 to become one of the most exciting players. Dixon was a member of Great Britain's 1972 World Cup winning squad and a Lions tourist Down Under in 1974.
Name: John Mantle
Position: Loose forward
Union: Newport League: St Helens, Salford, Leigh, Barrow, Keighley, Oldham, Cardiff Blue Dragons.
The under-19s triple-jump champion's pace and power made him a threat whether at prop, second row or loose forward and he was a major part in St Helens' cup quartet winning 1965/66 season. The three-times Challenge Cup winner played in 19 major finals for the Saints and starred for Great Britain on 13 occasions both at home and abroad while a member of the Lions Tour to Australia in 1966.