"In December and January to show this consistency is amazing," Guardiola told BBC Sport. "In this league every game is so difficult.
"It was an incredible performance. We played incredibly well in many areas. We conceded few chances. We didn't create much, but enough to win the game.
"People think if we won the last one 5-0, we will win this one 5-0. This is the real world, not a fairytale.
"You see Sheffield United are bottom of the table and realise how tough is the Premier League. We always struggle to beat them every season."
Sheffield United manager Chris Wilder to BBC Sport: "We're playing a world-class team who are on an incredible run. It's a long way back when you fall behind to Manchester City early on, but we gave ourselves a chance to get something out of the game at the end. Unfortunately we didn't.
"We've won a couple of games and had a couple of tight games against Spurs and City. From my point of view, we're alive.
"I'm scratching my head at times to understand the position we're in, but we have a belief, fight and togetherness that we can pick up a couple of wins before the end of the season.
"We will drop points, it's about how we overcome it. Hopefully we react good in the bad moments, which for sure are coming."