article: Former Leeds and England coach Tony Smith admits he was shocked by Kevin Sinfield's decision to switch codes but, on reflection, believes it could be an inspired decision. Sinfield, 34, the greatest captain in Leeds' history, stunned the world of rugby league with his sudden announcement that he will quit the sport at the end of the season and join the Rhinos' sister club Yorkshire Carnegie on an 18-month contract. Sinfield, who is closing in on third place in rugby league's all-time scoring list with 3,997 points, told a news conference at Headingley he did not want to play against Rhinos and that the opportunity to spearhead Carnegie's bid for a Premiership return was too good to resist. Leeds Rhinos captain Kevin Sinfield is to switch codes and join Yorkshire Carnegie at the end of the season . Sinfield (centre) lifts the Super League trophy after Leeds beat Warrington in the grand final in October 2012 . Warrington coach Tony Smith (left) speaks with fellow coaches Tony Rea and Brian McDermott . Smith, who was in charge of the Rhinos when Sinfield lifted the first of their six Super League titles in 2003, says he is sad to see his former skipper swap codes. 'I was a bit shocked,' Smith said. 'It took me a couple of minutes to think about it. He's a champion player, he's been a champion player for his club and his country for many years. 'I'm sad to lose him to that other code. However, I could understand the rationale. If it's a way of him plying his trade for longer - his trade of playing rugby and being a terrific professional - I can see why he's made that change. 'I think he'll have a lot to still contribute to their sport and to that club. It's not a huge switch for him in terms of training venues. 'He'll still have his bumps and bruises, but the fact that he can continue to do that and probably get well rewarded for it, I can't blame him.' Sinfield, whose bombshell announcement came just four days after his predecessor as England captain Jamie Peacock revealed he would be leaving Leeds at the end of the season to become football manager at Hull KR, has missed Leeds' last two games through injury and, according to Smith, is probably stepping down at the right time. Sinfield (left) in action for England against France during the 2013 Rugby League World Cup quarter-final . Sinfield is tackled during a match between Leeds Rhinos and Leigh Centurions last year . 'I think it's fantastic to make that decision to bow out of Super League probably at the right time,' Smith added. 'You can't keep playing forever and, when those young guys come snapping at your heels, it's hard to keep them at bay at some stage. 'You have to bite the bullet and step aside and I'd say the time is probably right. I'm no expert on when other people should retire but I'm pleased for Kevin and he'll certainly give everything he's got to his new employers. 'That's how he's been in rugby league and I've got no reason to think it'll be any different.' Sinfield has never played rugby union but already identified a role for himself in his new sport as he follows in the footsteps of Jason Robinson, Andy Farrell and Sam Burgess. 'Ideally I'd like to play fly-half,' Sinfield said. 'It's the position that suits the skill set I have the best. Sinfield and his Leeds team-mates celebrate after beating Melbourne Storm in the 2008 World Club Challenge . 'I understand the challenge that's in front of me and the difficulties rugby league players have faced crossing over. That's why I think I'm in the best possible place to help with that transition. 'Playing union is something I've always wanted to do. I didn't want to end my career and have regrets about missed opportunities. When this opportunity came up I knew it was the right thing. 'I'm excited by it. I know the potential at the club and it's something I'd like to be a part of. 'I'm very respectful of the game and I like watching it. I think a lot of rugby league people look down on rugby union, and I think a lot of rugby union people look down on rugby league. But I like both games. As a sportsman, to get the opportunity to play another professional sport is something that really appeals to me.'
highlights: Kevin Sinfield has announced he is leaving Leeds at the end of the season .
  The 34-year-old will cross codes to join sister club Yorkshire Carnegie .
  Sinfield has won six Super League titles, three World Club Challenges and one Challenge Cup with the Rhinos .
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