The west London club started the new campaign with a victory and their summer signing from RB Leipzig was involved in the opener, with Werner brought down by goalkeeper Mat Ryan and Jorginho dispatching the resulting spot-kick.
Brighton played well and levelled the score in the second half, but a stunning effort from Reece James followed by a rather more fortuitous one from Kurt Zouma wrapped up three points.
Although Pulisic had returned to training last week and appeared in contention to play, he did not make the matchday squad with Lampard confirming that the hamstring injury picked up against Arsenal in the FA Cup final is still affecting him.
Asked why the American was absent, Lampard explained: ‘Christian was training with us last week but he had a bit of discomfort a couple of days ago when he was trying to be in contention for today.
‘It would have been a big ask for today and he has had to take a few steps back and we will have to see.’
On Werner, Lampard said: ‘He took a knock when he won the penalty which we hope is a dead leg.
‘I would like to think if it is that we have a bit of time to get him back [for the Liverpool game].’
On Jorginho he added: ‘Jorginho is just tiredness. A lot of players are not fully fit at the moment and that is just the way it is.
‘I thought they dealt with the rigors of the game very well in terms of how tough it is to come to Brighton when you are not quite there.’