Chelsea had the opportunity to go six points clear of second-placed Manchester United, who lost 3-0 at Fulham on Saturday, against a struggling West Ham side scrapping for their lives near the foot of the table.
"One more point is four points ahead which is good because we didn't play a good match," the Italian told the club's website after the London derby.
"For every team ... it is not the best period. There are a lot of games and if you play every three days it's not easy," said Ancelotti after Frank Lampard's thrice-taken penalty in the second half cancelled out Alessandro Diamanti's 45th-minute spot-kick.
"I don't think Chelsea is in the best moment but they are not the only ones. They have what it takes to win the title," said the Italian.
"I know Greeny from England, we practice," said Lampard.
"It's a bit of mind games really, you keep wondering whether you should go to the same side (of the goal) again."
