Ballinamallard United duo Mark Stafford and David Kee have signed pre-contract agreements with Linfield.
The club said defender Stafford and midfielder Kee turned down contract extensions in order to join the Blues.
"We are extremely disappointed at the decision that both players have made, but it is one that we must respect" added the club in a statement.
Donegal Celtic defender Danny Wallace has also signed a pre-contract agreement with Linfield.
Stafford and Kee helped the Mallards retain their Premiership status this season.
Kee, 26, ends a six-year spell with the team while United boss Whitey Anderson has coached Stafford since he was a boy.
"Between them they have made about 500 appearances for the club in the Championship and Premiership," said Anderson.
"They are two fine young men with great ability and integrity who, when offered chances to leave Ballinamallard as early as the January window of our first season in the Premiership, declined and instead embraced the opportunities that Ballinamallard offered them.
"They were under no obligation to stay at Ferney Park for three Premiership seasons, and the fact is that they enjoyed playing for Ballinamallard and were always looked after extremely well here. "
Linfield manager Warren Feeney said he was "delighted" to bring Stafford, 27, and Kee to Windsor Park.
"They are two players who we've been looking at for a while and I'm thrilled that we've been able to secure their signings ahead of next season," he told the club website.
"Mark is an experienced player and leader in this league and he's a strong defender who the club tried to sign before, so it's great news that he's agreed to join us at this time.
"David is another player who knows the league well and I know there were several other clubs that were interested in signing him, so I'm delighted that he too has agreed terms to join us over the summer. He will add steel to the squad."