Brighton came into this contest looking to avoid a third consecutive league defeat and the way they celebrated with their fans at the final whistle suggests that the humiliating 7-0 loss at Nottingham Forest has been quickly cast aside.
They were sharp in and out of possession and had a focal point up front unlike Chelsea, with Nicolas Jackson's absence keenly felt as the visitors failed to muster a shot on target despite attempting 717 passes to Brighton's 320.
The hosts also showed greater intensity to win the ball back in key areas with Chalobah's rushed clearance contributing to their second goal, and Welbeck pressuring Levi Colwill into a mistake for the third.
While Chelsea were only narrowly beaten in the FA Cup, this was a far more humbling experience, with Veltman threatening to add to their miserable trip to the south coast late on, when he hit the post.
On this evidence there are plenty of issues for Maresca to address, with the Italian labelling his team's display as their "worst" since he took the helm last summer.
"The performance is not one you want to offer so we are very upset and sorry for the fans that were here," Maresca said.
"They are completely right to be upset, especially in this moment of the season. To come here and play in the way we played, not on the ball, in terms of desire, we probably need to show more."
Noni Madueke limped off early on to add to Chelsea's growing injury woes and Palmer, whose sparkling form has helped carry the club into a position to compete for a Champions League place, appeared out of sorts.
Marc Cucurella looked vulnerable down their left, with Madueke's replacement Jadon Sancho struggling to make any impact and the defensive errors that have underpinned their season were again evident to see.