Terry O'Connor told Boots 'n' All that Wigan new boy Andy Powell could take time to get to grips with Super League.
Welshman Powell will join up with the Warriors in June after sealing a switch from rugby union outfit Sale and penning a deal until the end of the 2015 campaign.
The 31-year-old has enjoyed a glittering career in the 15-man code, making 23 appearances for his country since debuting against South Africa five years ago and touring the Springbok nation in 2009 with the British and Irish Lions.
However, O'Connor says he has seen first-hand the travails union players can encounter when joining league after teaming with Wales legend Scott Quinnell in the 1990s, and he thinks Powell could find things equally tough in his new surroundings.
"Powell is big, aggressive and has played the game at the top level," said O'Connor. "But he is coming in at over 30 years of age and the big difficulty for him will be the speed of the game and the speed at which players will be running at him.
"He will be targeted because he is a big bloke who may not be as agile; I don't have a problem when the ball is in his hand because he will steamroller people, but the defence in rugby league is what catches out some of the union boys.
"I remember playing with [Scott] Quinnell when he came to Wigan and it took him two years to get up to speed with the game because he was playing in the middle of the park and found it very difficult to get up the park, back again, reset and condition his body."
Wigan's acquisition of Powell was tempered by the news that England internationals Lee Mossop and Gareth Hock - the latter of whom is currently on a season-long loan at Widnes - will join NRL franchise Parramatta Eels for the 2014 campaign.
Key man Sam Tomkins could also depart the Warriors in the next few years, with the cub's chairman Ian Lenagan saying a transfer to New Zealand Warriors may be in the pipeline.
And Boots pundit John Kear admits he is worried for the future of Super League if the division's star players continue to flock Down Under in search of a fresh rugby-playing experience.
"It is really positive that a rugby union star (Powell) is coming to rugby league, but we really have to do something about the exodus of our players to the NRL and make it more financially lucrative to stay in our competition," said the Batley Bulldogs coach.
"It's alright saying it will benefit the international team [for England team members to play in Australia] but we need our best players playing in our competition as our fans pay to watch the elite - and our elite is guys like Tomkins, Mossop, and Hock.
"I don't want to see our best international players - especially Tomkins, who is box office and regularly produces very special stuff - for three or four weeks at the end of the season.
"I want to see them strutting their stuff throughout the season and showing us exactly how good they are."