Crouch says it's vital Modric and the rest of the club's star names stay at White Hart Lane if Spurs are to achieve their goal of playing in the Champions League once again.
Crouch said: "I think it will be the most open Premier League for a while next year and of course you have to hold on to your best players.
"If you want to improve you have got to add to the players you already have got but I'm sure that the manager and chairman will be sorting things out over the summer and hopefully we have a real good season next year.
"There's no doubt in the world that every team are going to make themselves stronger and we can't fall behind.
"I'm sure that the manager and chairman have got plans in mind of who they will want to bring in and add that little bit of quality that takes us to maybe that next step."