Peter Houston's decision to leave Dundee United at the end of the season was announced on Thursday, ahead of the Taysiders' visit to Rugby Park in the SPL.
Houston had been in talks with the Tannadice side over a new deal, but at a joint press conference with chairman Stephen Thompson, he revealed he has decided against extending his contract on reduced terms.
Speculation began immediately with regards who would succeed the former Scotland assistant, with ex-United skipper Derek McInnes, who recently departed Bristol City, installed as favourite by one bookmaker.
Killie boss Shiels, though, insists the United players are too professional to be affected and will also be playing to impress their future boss, whomever it may be, when the Scottish Premier League resumes after the winter break.
He said: "I think Peter has done magnificent there, but it won't affect the players because they have quality players right through the team.
"So I can't see it having an adverse impact on the team, they are too professional.
"I can see it having a type of 'let's play for our places because there could be a new manager who comes in who might not like us'.
"Dundee United played really well against us at Tannadice in the last game when it was 3-3.
"We were 2-0 up and 3-1, but they came back and got a goal at the end of the game and thoroughly deserved it.
"They have a fantastic team and great players."
Shiels may have more to be concerned about with his own squad after losing three players, with the threat of more to follow.
Stopper Michael Nelson completed his switch to Bradford on Wednesday, midfielder Liam Kelly joined Bristol City last week, while striker Rory Boulding has left the club.
"You obviously have to cut your cloth and I'm not going to complain," said Shiels.
"We might be affected the most but we can't start crying because it sends out negative energy, and we don't want that to happen.
"They are massive losses but there is an opportunity for others to step up. We have good people to come in.
"I am motivated towards getting young boys in to help develop their careers and the club accordingly. That's the motivation I have.
"There could be more players leaving. I have no problems with that. If a player wants to leave he can.
"But hopefully this is a good enough place for people not to want that."