Celtic boss Brendan Rodgers has accused "some people" of trying to "dismantle" his relationship with the club's board.
They then scored two late goals on Saturday to beat Championship side Partick Thistle 3-1 in the League Cup.
Rodgers said the transfer situation was "very simple".
Speaking to BT Sport, he said: "We've had a couple of targets we haven't been able to get.
"But I've always had a very, very good relationship with the board and that's the same, even though some people will try to dismantle that.
"We want to improve the team and we've got 'til the end of August to do that. If we don't, I work with the talented players we have here."
- Under-pressure Celtic survive scare at Thistle
- Reaction & how the game unfolded
- Rate the players: pick your man of the match
- Can you name the last 15 League Cup winners?
Two goals in two minutes from Moussa Dembele and Tom Rogic ensured Celtic progressed to the last eight with victory at Firhill, after Andrea Mbuyi-Mutombo had cancelled out Leigh Griffiths' opener.
Rodgers admits his side "didn't play well" but was pleased to end a "difficult week" with a win.
"I was more concerned with our performance," the Celtic boss, who has guided the club to back-to-back domestic trebles, told BBC Scotland.
"Our pressing was too passive and our identity is very much around aggression and intensity in our press and we were nowhere near that.
"It's been a brilliant couple of seasons here and we can still have that this season. But on the back of a long week, it's something that can prey on the players' mind but this will be good for their confidence."