Liam Polworth admits Inverness team-mates James Vincent and Danny Williams will be difficult to replace after the midfield pair pledged their futures to Dundee.
The Englishmen have followed Nick Ross in moving from Caley Thistle to Dens Park after the home-grown midfielder went the same way last year.
Both players have signed pre-contract agreements to move to Dundee at the end of their third season in the Highlands.
Vincent netted the winner in last season’s Scottish Cup final and would have made a bigger impact in the league but for several injuries, while Williams recently played his 100th game for the club.
A new contract at Caledonian Stadium had been on the table for Williams, 28, who has been a regular for John Hughes’ side this season, making 35 appearances.
Hughes recently said he could not justify offering Vincent a new contract, however, given the 26-year-old’s struggles with a knee injury, with the last of his 16 appearances this term coming in the 2-0 win against Ross County on January 2.
Hughes also claimed he was not able to match the offers tabled by Dundee several weeks ago, which was denied by counterpart Hartley.
Polworth said: “It’s a big blow to lose two first-team players. Vinny scored the goal in the Scottish Cup final and he’ll always be a part of Inverness.
“Danny can play him anywhere and he will go out and give you 100%.
“So, to replace two quality players like that will be a tough job. I’m just glad it’s not my job.”
Polworth made himself a first-team regular with some impressive displays after the summer departure of Ross and Inverness manager John Hughes will need to look for replacements again.
Hughes has also seen Ryan Christie, Graeme Shinnie and Billy Mckay end up at Premiership rivals this season, while Inverness fended off Aberdeen’s bid for Greg Tansey in January.
Polworth said: “Sometimes you are a victim of your success: players do well and they move on and then you have got to start all over again.”