Macclesfield won 2-1 to dump the holders out of the competition.
Guéhi said after the defeat: “Credit to Macclesfield, credit to their club, and to their players for how well they played, their level of intensity – congratulations to them.
“I'm just going to give absolute praise to Macclesfield – for their fans, and for the way they played. It’s obviously an incredible story for them. Congratulations to them, and I wish them well in the competition.
“Today, we didn’t approach the game in the way we would have hoped, but credit to Macclesfield. They were the better team, they wanted it more, they were more aggressive.
“We won it last year, and again, if we're being honest, miracles can happen, and another miracle happened today.
"It's the FA Cup. It's kind of what the competition's about, I guess.”