Orlando City manager Adrien Heath has warned Steven Gerrard and Frank Lampard that the MLS is a very competitive league.
Gerrard and Lampard are due to move across the Atlantic to turn out for MLS sides in the summer, with Heath insisting that the league is not just a route to help footballers extend their careers.
"The days of coming over at 35 and thinking it's going to be nice and easy for the last two or three years of your career are long gone. That's finished," said Heath, according to The Mirror.
"If you cannot still run around and have a competitive edge then it's not going to work for you. American players are very athletic, committed and determined and the league is difficult.
"The most important thing is when these players come over - the Thierry Henrys, the Lampards, the Gerrards, the David Villas - they come over and want to play and do well. The players in England have to understand it is a very competitive league."
Heath's City side will feature Brazilian legend Kaka in their ranks this MLS season.