Oli Marns will lead a Halifax rugby invasion of London this weekend, in the process creating a small slice of cross-code history. Marns is in one of the two Halifax teams on the supporting card for today's rugby union Powergen Cup final between Northampton and London Irish at Twickenham. But he will have to limit his post-match activities, as the 23-year-old wing earns his money with the Halifax Blue Sox, and is in their squad for tomorrow's tough Tetley's Super League match against the London Broncos in Brentford.

Marns admits he is no Jason Robinson, but even Billy Whizz did not manage to combine a union cup final at Twickenham with a Super League match on the same weekend. "It's going to be pretty hectic, but playing on the wing it shouldn't be too bad," he said.

"I'm not too bothered about the history, but I shouldn't think it's been done before because it's not so long since they wouldn't let a rugby league player within 100 miles of Twickenham. Obviously the standard of rugby is going to be higher in the Super League game against the Broncos, but I'm really excited about playing at Twickenham. I can't wait."

The rugby league influence at Twickers today extends well beyond Marns. David Brook, who bankrolled the Halifax team that won the championship in 1985 and beat St Helens in the Challenge Cup final at Wembley the following year under the coaching of Chris Anderson, is now the president of the rugby union club, who face Gosport in the Intermediate Cup final.

Heath, the other Halifax club in action today, against Bromley in the Junior Vase final, are coached by the former Blue Sox second-row Carl Gillespie, who retired three years ago to work in the fire service.

The Rotherham team who play Exeter in the Powergen Challenge Shield final have Mike Umaga, a Samoan who was a popular figure for the Blue Sox in the first two seasons of summer rugby, as their player-coach.

Even the main game will have its league interest, as Warrington's Australian performance director Steve Anderson has spent time working with the London Irish defence, and Northampton will have the former Penrith Panthers player Peter Jorgensen in the centre - with two old mates from Sydney, the current Blue Sox recruits Robbie Beckett and Dave Woods, watching with the rest of the Halifax league team in the stands.

The relationship between the two codes has come a long way since Wigan stormed Twickenham to win the Middlesex Sevens in 1996, and that leaves young players like Marns with a number of extra options to consider.

"My contract with the Blue Sox is up at the end of this season, and after that I'm open to offers from any code, anywhere in the country," he said.

A 22-year-old law graduate from Leeds University - who, unusually in the Super League, managed to combine his studies with his rugby career - Marns is also looking for "a proper job" now that he's nearly finished his masters.

"I'm definitely a rugby league man, that's the game I grew up watching," he explained.

"But there might be more chance to play a bit of part-time union and combine that with starting a career in the law."

Who knows, the London Broncos may even step in, just as they did this winter with the Cambridge graduate, Scotland international and former Hunslet centre Iain Higgins.

But Marns's case does raise some questions which must concern the rugby league authorities. First, he's been given permission to play rugby union by Halifax's Australian coach Steve Linnane - "basically as a way of staying fit now that there is no reserve-team competition, which is a barmy decision" - and he is far from the only player who has been driven to the other code by the decision to scrap the Alliance.

Second, the main reason Marns has been struggling for a place in the Blue Sox team this season is that Halifax have signed three Australian three-quarters - Woods, Beckett and Calum Halpenny, who is exempt from the overseas quota because of Irish ancestry.

Halifax have exploited that loophole to start several games with only four British players in their starting 13, and as Marns says: "The player in my position [Halpenny] they've flown 12,000 miles from the Parramatta second team, and once they've gone to the expense of bringing him, they're not going to leave him out."

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