Chelsea have opened up a seven-point lead at the top of the table, but Ramires admits there is no room for complacency.
The Blues find themselves in a commanding position in the race for the Premier League crown, with a 4-0 derby victory over Tottenham Hotspur on Saturday edging them further clear of the chasing pack.
Jose Mourinho's men have, however, taken in more fixtures than all of their fellow title chasers.
Liverpool and Arsenal are one game back, while Manchester City now hold three games in hand.
Were City to take maximum points from those outings, they would pull level on points with Chelsea and climb to the summit courtesy of their superior goal difference.
With there still all to play for entering the final sprint to the finish, Ramires acknowledges that Chelsea have little margin for error despite being the side in pole position.
He told Globo Esporte: "Manchester City have games in hand and a lot can happen.
"We have to keep focusing on a game at a time, we can't fall into the trap of thinking that everything is okay.
"Any slip-up could be fatal at this point in the league."
If Chelsea are to come out on top, they need everyone at Stamford Bridge to pull together.
That would appear to be the case at present, with Ramires quick to hail the role an expectant fan base is playing in the pursuit of domestic honours.
The Brazil international added: "The fans at Stamford Bridge have been our 12th player, they are creating an atmosphere which really helps our team.
"It's hard not to be excited right now but there is still a lot to be done before we can talk about the title."