The Blues had climbed to within two points of leaders Liverpool on the back of five consecutive wins before a disappointing 0-0 draw at Everton was followed by Fulham's first win at Stamford Bridge since 1979.
Chelsea are now seven points adrift of the Reds, who also have a game in hand.
Maresca's men had lost just two league games previously this season to Manchester City on the opening weekend of the season and Liverpool in October.
The Italian had always insisted his young squad was not yet ready to challenge for the title but is hoping for a reaction at Ipswich on Monday.
"We never thought we would win every game," said Maresca.
"We lost on August 18, and then after two months, and then after two months. But we know the reality is not just to lose one game every two months. It's a matter of how we react and try to go again."
Maresca has lent on Chelsea's huge squad to great effect in the Europa Conference League to cruise into the knockout stages without dropping a point from six games.
Those that have impressed in Europe could be in line for a rare opportunity in Premier League action at Portman Road during a hectic festive period for English clubs.
Maresca made seven changes for a 5-1 win at Southampton earlier this month during a similarly congested spell.
"For sure we are going to change something," he added.
"After a game you need to go again, no matter the result. Especially this month.
"We have already played eight or nine games in December, in 26 or 27 days. Now it's also important to recover the energy and go again on Monday."
England international Noni Madueke is among those in contention to return after he was surprisingly dropped from the squad entirely against Fulham.
Maresca told Madueke earlier in the season to up his levels in training and expects a similar reaction to when he scored against Southampton just days after being dropped for a 3-0 win over Aston Villa.
"Is he in contention for Ipswich? Yeah, for sure," said Maresca.
"He responded very good at that time so there is no more than that. I expect the same this time, absolutely."
