Modric is understood to be signing for Manchester United after Croatia's campaign is over.
"I told Luka before Euro 2008 that there were better-known midfield players in the tournament but, for me, he was the best. I told him that and he played great," Bilic said.
"I expect the same now. I wouldn't swap him for any midfielder, no way. Xavi and Iniesta have more trophies but Luka is in that category. It's been a hard season after the pressure of transfer speculation. He played well but then had a few dodgy games like the rest of the Spurs team.
"There was never any rotation with Luka, he was too important. Luka has to cope with the pressure of being our star man, and he can. We have prepared him physically and psychologically. He was young at Euro 2008. Now he's one of our senators."