All four missed the midweek Champions League win over Schalke, with Mendy and Delph having not featured since January’s semi-final win at Burton Albion.
Guardiola explained that the quartet are recovering well but declared he will decide on Saturday afternoon whether each of them will be fit to face Chelsea at Wembley on Sunday.
“Today, we were off,” he stated. “We didn’t train, so tomorrow, we will see.
“The info we had from the doctors says that they are getting better but right now, I cannot tell you.”
On Delph, he explained: “He was injured many times in the period – although it was not a big problem – and in the last days, he was sick.
“The recovery was not good and that was the reason why. The other reason is that I trust Oleks Zinchenko in that position.”
Guardiola also explained he is yet to choose which goalkeeper to field, with Aro Muric having featured in the previous rounds of the competition.
“We will see,” he continued. “Muric is incredible in penalty shoot-outs and that’s why we trust him and why he is the second ‘keeper for City.”
With the Blues seeking to retain the League Cup, Guardiola also spoke of the boost winning a trophy in February can provide, ahead of the run-in – as it did last season.
The Catalan boss also warned of a Chelsea backlash, following the Champions’ 6-0 triumph at the Etihad Stadium earlier this month.
“It was really important [to win the Carabao Cup],” he declared. “In the Premier League, we were flying in that period but in the days before, we went out of the FA Cup at Wigan.
“It is not the most important title but we are here, playing at Wembley – a magical stadium, against a top side in Chelsea.
“In the moment, I was so happy but today, I wish we hadn’t beaten them 6-0!
“I don’t like to play one team in a short period of time, after you've beaten them. They are professional players and they will go extra.
“When we lost 2-0 at Stamford Bridge, we couldn’t accept defeat at home. We will prepare as much as possible.
“We are going to prepare to win and try to enjoy it, and compete well. We have to play a good game to win.”
Guardiola also offered his well wishes to the City fan injured in Germany, following Wednesday’s Champions League victory at Schalke.
“We knew the day after – it is terrible news for the family,” he said.
“The game was spectacular but unfortunately, this happened and our thoughts and wishes from all of us go to them.
“It’s tough and hopefully, the police can sort the problem and he gets well as soon as possible.”